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Examining the science of global warming skepticism, clearing up the misconceptions and misleading arguments that populate the climate change debate.
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2017 SkS Weekly Climate Change & Global Warming Digest #46

November 19, 2017 - 1:19pm

Story of the Week... Toon of the Week... Quote of the Week... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

UN Climate Talks Wrap Up with World Leaving Trump Behind

‘However much Trump wants to take us backward on climate change, the rest of the world — and the rest of the U.S. — is intent on moving forward.’

 

While protesters outside the UN climate talks urged an end to coal, a broad range of climate supporters spoke up inside, including U.S. states, cities and businesses that support great global ambition to rein in climate change. Credit: Sascha Schuermann/AFP/Getty Images 

Two weeks of international climate talks in Bonn made only incremental progress toward resolving disputes that have been lingering since the Paris Agreement of 2015. The main achievement may have been cementing a firebreak to prevent the Trump administration from torching the whole process.

The strategy is to assert a broad new leadership among nations big and small, to bolster their resolve with high-profile commitments from American cities and states, to muster corporations and financial institutions in an attempt to kickstart renewable energy and assist poor countries, and to leave Washington isolated on the world stage.

It's a strategy pinned on the hopes—although diplomats would never put it so bluntly—that either Donald Trump will change his mind or that the United States will change its leader.

"The story of these climate talks was that however much Donald Trump wants to take us backward on climate change, the rest of the world—and the rest of the U.S.—is intent on moving forward," said Nathaniel Keohane, vice president for global climate at the Environmental Defense Fund. 

UN Climate Talks Wrap Up with World Leaving Trump Behind by John H Cushman Jr, InsideClimate News, Nov 16, 2017 

Toon of the Week...

 

Quote of the Week...

“This is the worst moment for the Americans to start behaving like a five-year old all of a sudden,” Christian Ehler, a German member of the European Parliament who speaks on EU and U.S. relations at the climate change talks, said in an interview. “The leader of the western world is stepping out of the multilateral framework used to tackle the most dramatic problem the world might be facing in the next 100 years.” 

U.S. Is Acting ‘Like a 5-Year-Old’ Over Global Warming, EU Official Says by Jess Shankleman, Bloomberg News, Nov 17, 2017

Coming Soon on SkS...
  • Pummeled by extreme weather, Americans are growing concerned about climate change (Dana)
  • Analysis: WRI data suggests emissions have already ‘peaked’ in 49 countries (Zeke Hausfather)
  • Guest Post (John Abraham)
  • Impact of climate change on health is ‘the major threat of 21st century’ (Daisy Dunne)
  • New research this week (Ari)
  • 2017 SkS Weekly Climate Change & Global Warming News Roundup #47 (John Hartz)
  • 2017 SkS Weekly Climate Change & Global Waming Digest #47 (John Hartz)
Poster of the Week...

 

Climate Feedback Reviews...

 

Climate Feedback asked its network of scientists to review the article, The three-degree world: the cities that will be drowned by global warming by Dom Phillips, Helen Roxburgh, Jonathan Watts, Josh Holder, Justin McCurry, Niko Kommenda, Richard Luscombe & Ruth Michaelson, Guardian, Nov 3, 2017

A majority of reviewers tagged the article as: Insightful and  Misleading.

Review Summary

This story in The Guardian includes maps of, and reporting from, five coastal cities that will be affected by continued sea level rise. The story discusses the impact sea level rise will have on those cities, and what they are doing to prepare and adapt.

However, scientists who reviewed the story found that it fails to explain one very important thing to readers: nowhere is it explained that the magnitude of sea level rise shown (for a scenario in which the world warms by 3 °C) is the amount that would occur after the planet has had centuries to millennia to come into equilibrium with elevated temperatures. Readers are likely to assume that the story’s maps illustrate sea level rise that could occur before the end of the 21st century, but this is not the case.

See all the scientists’ annotations in context

UPDATE (15 November 2017): The article has been updated to include some explanation in an expandable box. It states, in part, “How quickly will oceans rise? It could take decades or centuries, but change will be locked in by a 3C temperature rise, which would extensively melt ice caps, shrink glaciers and thermally expand the oceans so many current coastlines and low-lying plains would be under sea level.”

Guardian explores sea level rise impact on cities, but fails to make timescale clear, Climate Feedback, Nov 10, 2017

SkS Week in Review...  97 Hours of Consensus...

 

 

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2017 SkS Weekly Climate Change & Global Warming News Roundup #46

November 18, 2017 - 11:18am
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week.  Editor's Pick

‘Planet at a crossroads’: climate summit makes progress but leaves much to do

The UN negotiations in Bonn lay the groundwork for implementing the landmark Paris deal, but tough decisions lay ahead

Representatives of Act Alliance hand out chocolate coins, promoting the need for climate finance for adaptation. Photograph: Kiara Worth/ENB/IISD

The world’s nations were confident they were making important progress in turning continued political commitment into real world action, as the global climate change summit in Bonn was drawing to a close on Friday.

The UN talks were tasked with the vital, if unglamorous, task of converting the unprecedented global agreement sealed in Paris in 2015 from a symbolic moment into a set of rules by which nations can combine to defeat global warming. Currently, the world is on track for at least 3C of global warming – a catastrophic outcome that would lead to severe impacts around the world.

The importance of the task was emphasised by Frank Bainimarama, Fiji’s prime minister and president of the summit: “We are not simply negotiating words on a page, but we are representing all our people and the places they call home.”

‘Planet at a crossroads’: climate summit makes progress but leaves much to do by Damian Carrington, Guardian, Nov 17, 2017 

Links posted on Facebook

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Fri Nov 17, 2017

Sat Nov 18, 2017

New research, November 6-12, 2017

November 17, 2017 - 4:10pm

A selection of new climate related research articles is shown below.

The figure is from paper #32.

Climate change impacts

1. Nitrogen availability dampens the positive impacts of CO2 fertilization on terrestrial ecosystem carbon and water cycles

"Results suggest that the rate of global GPP increase is overestimated by 85% during 2000-2015 without N limitation. This limitation is found to occur in many tropical and boreal forests, where a negative leaf N trend indicates a reduction in photosynthetic capacity, thereby suppressing the positive vegetation response to enhanced CO2 fertilization."

2. Climatic variability and dengue risk in urban environment of Delhi (India)

"Findings reveal significant changes in weather across the year having significant and positive association with dengue cases at specified lags. Weeks in April and July to October with gaps have been identified as the high risk weeks based on the estimated relative risk. There has been intra-annual expansion in dengue risk period extending beyond monsoon and post-monsoon."

3. Introduction to Special Issue: Disciplinary Perspectives on Climate Change and Conflict

"These authors find little evidence for direct pathways from climate change to violence, especially for group-level violence and armed conflict. However, there is stronger evidence for indirect effects in agricultural and other vulnerable settings and for exacerbating ongoing violence rather than initiating new violence. The authors also emphasize the importance of governance and institutions, adaptive capacity, and potential cooperative behavior in moderating violence."

4. Flood vulnerability, local perception and gender role judgment using multivariate analysis: A problem-based “participatory action to Future Skill Management” to cope with flood impacts

5. Risk perception and adaptive responses to climate change and climatic variability in northeastern St. Vincent

6. Does weather forecasting relate to foraging productivity? An empirical test among three hunter-gatherer societies

7. Climate change impact on the potential yield of Arabicacoffee in southeast Brazil

8. Potential rice exposure to heat stress along the Yangtze River in China under RCP8.5 scenario

9. Influence of climate variability and length of rainy season on crop yields in semiarid Botswana

10. Increasing drought and diminishing benefits of elevated carbon dioxide for soybean yields across the US Midwest

11. The effects of projected climate and climate extremes on a winter and summer crop in the southeast USA

12. Irrigation offsets wheat yield reductions from warming temperatures

13. Temperature-mortality relationship in dairy cattle in France based on an iso-hygro-thermal partition of the territory

14. Impacts of temperature extremes on European vegetation during the growing season

15. Vegetation phenology on the Qinghai-Tibetan Plateau and its response to climate change (1982–2013)

16. Rapid responses of plants to temperature changes

17. Lags in the response of mountain plant communities to climate change

18. Emerging stress and relative resiliency of Giant Sequoia groves experiencing multi-year dry periods in a warming climate

19. Nitrogen limitation of decomposition and decay: how can it occur?

20. Impacts of warming and nitrogen addition on soil autotrophic and heterotrophic respiration in a semi-arid environment

21. Carbon cycle confidence and uncertainty: exploring variation among soil biogeochemical models

22. Multidecadal fCO2 Increase Along the United States Southeast Coastal Margin

23. The fatty acid content of plankton is changing in subtropical coastal waters as a result of OA: Results from a mesocosm study

24. Ocean acidification does not impair predator recognition but increases juvenile growth in a temperate wrasse off CO2 seeps

25. Participatory scenario planning and climate change impacts, adaptation and vulnerability research in the Arctic

Climate change mitigation

26. How much do direct livestock emissions actually contribute to global warming?

"We find that direct livestock non-CO2 emissions caused about 19% of the total modelled warming of 0.81°C from all anthropogenic sources in 2010. CO2 from pasture conversions contributed at least another 0.03°C, bringing the warming directly attributable to livestock to 23% of the total warming in 2010."

27. Role of e-reader adoption in life cycle greenhouse gas emissions of book reading activities

"Adopting e-readers was discovered to reduce both the GWP per person and the GWP per person-book of book reading activities. The GWP of e-books read with an e-reader and the GWP of paper books were found to break even at 4.7 books per year, provided consumers read less than 11 h a day. According to the web survey, e-reader users purchase more than seven e-books annually on average, which resulted in a smaller GWP per person-book relative to that of one paper book."

28. Climate change, future Arctic Sea ice, and the competitiveness of European Arctic offshore oil and gas production on world markets

"We find that under current hydrocarbon prices, oil and gas from the European offshore Arctic is not competitive on world markets."

29. Variability and correlation of renewable energy sources in the Portuguese electrical system

30. Diurnal and seasonal variations of greenhouse gas emissions from a naturally ventilated dairy barn in a cold region

31. Can abandoned peatland pasture sequestrate more carbon dioxide from the atmosphere than an adjacent pristine bog in Newfoundland, Canada?

32. Outdoor cooking prevalence in developing countries and its implication for clean cooking policies

33. An initial scoping of transitional justice for global climate governance

34. Climate Engagement in a Digital Age: Exploring the Drivers of Participation in Climate Discourse Online in the Context of COP21

35. Politicization of science: how climate change skeptics use experts and scientific evidence in their online communication

36. Uncertainties in modelling the climate impact of irrigation

37. Greenhouse Gas Emissions under Different Drainage and Flooding Regimes of Cultivated Peatlands

38. Reduction of solar photovoltaic resources due to air pollution in China

Climate change

39. Changing world extreme temperature statistics

"In contrast to this earlier work, we find that in every region except North America all-time high records were set at a rate significantly (at least 3σ) higher than in the null hypothesis of a stationary climate. Except in Antarctica, all-time low records were set at a rate significantly lower than in the null hypothesis. In Europe, North Africa and North Asia the rate of setting new all-time highs increased suddenly in the 1990s, suggesting a change in regional climate regime; in most other regions there was a steadier increase."

40. An energy balance model exploration of the impacts of interactions between surface albedo, cloud cover and water vapor on polar amplification

"We examine the effects of non-linear interactions between surface albedo, water vapor and cloud cover (referred to as climate variables) on amplified warming of the polar regions, using a new energy balance model. Our simulations show that the sum of the contributions to surface temperature changes due to any variable considered in isolation is smaller than the temperature changes from coupled feedback simulations. This non-linearity is strongest when all three climate variables are allowed to interact. Surface albedo appears to be the strongest driver of this non-linear behavior, followed by water vapor and clouds. This is because increases in longwave radiation absorbed by the surface, related to increases in water vapor and clouds, and increases in surface absorbed shortwave radiation caused by a decrease in surface albedo, amplify each other. Furthermore, our results corroborate previous findings that while increases in cloud cover and water vapor, along with the greenhouse effect itself, warm the polar regions, water vapor also significantly warms equatorial regions, which reduces polar amplification. Changes in surface albedo drive large changes in absorption of incoming shortwave radiation, thereby enhancing surface warming. Unlike high latitudes, surface albedo change at low latitudes are more constrained. Interactions between surface albedo, water vapor and clouds drive larger increases in temperatures in the polar regions compared to low latitudes. This is in spite of the fact that, due to a forcing, cloud cover increases at high latitudes and decreases in low latitudes, and that water vapor significantly enhances warming at low latitudes."

41. Recent Advances in Our Understanding of the Role of Meltwater in the Greenland Ice Sheet System

"There have been dramatic increases in surface meltwater generation and runoff since the early 1990s, both due to increased air temperatures and decreasing surface albedo. Processes in the subglacial drainage system have similarities to valley glaciers and in a warming climate, the efficiency of meltwater routing to the ice sheet margin is likely to increase. The behaviour of the subglacial drainage system appears to limit the impact of increased surface melt on annual rates of ice motion, in sections of the ice sheet that terminate on land, while the large volumes of meltwater routed subglacially deliver significant volumes of sediment and nutrients to downstream ecosystems."

42. Unveiling aerosol–cloud interactions – Part 1: Cloud contamination in satellite products enhances the aerosol indirect forcing estimate

"We find that previous satellite-based radiative forcing estimates of aerosol–cloud interactions represented in key climate reports are likely exaggerated by up to 50 % due to including retrieval artefacts in the aerosols located near clouds. It is demonstrated that this retrieval artefact can be corrected in current products."

43. On the emergent constraints of climate sensitivity

"The relationships between the contrived metrics and ECS can also be linked statistically to shortwave cloud feedback. Thus any proposed or forthcoming ECS constraint based on the current generation of climate models should be viewed as a potential constraint on shortwave cloud feedback, and physical links with that feedback should be investigated to verify that the constraint is real. In addition, any proposed ECS constraint should not be taken at face value, since other factors influencing ECS besides shortwave cloud feedback could be systematically biased in the models."

44. A consistent sea-level reconstruction and its budget on basin and global scales over 1958-2014

"The global-mean sea-level reconstruction shows a trend of 1.5±0.2 mm/y over 1958-2014 (1σ), compared to 1.3±0.1 mm/y for the sum of contributors. Over the same period, the reconstruction shows a positive acceleration of 0.07±0.02 mm/y2, which is also in agreement with the sum of contributors, which shows an acceleration of 0.07±0.01 mm/y2."

45. The impact of bias correction and model selection on passing temperature thresholds

46. Exceptional airmass transport and dynamical drivers of an extreme wintertime Arctic warm event

47. The role of humidity in determining scenarios of perceived temperature extremes in Europe

48. Warming across decades and deciles: minimum and maximum daily temperatures in China, 1955–2014

49. Variations in North Pacific sea surface temperature caused by Arctic stratospheric ozone anomalies

50. How uncertainty in field measurements of ice nucleating particles influences modeled cloud forcing

51. Simulated changes in aridity from the last glacial maximum to 4xCO 2

52. Comparison of various drought indices to monitor drought status in Pakistan

53. Seasonal predictability of Kiremt rainfall in coupled general circulation models

54. Scale dependency of regional climate modeling of current and future climate extremes in Germany

55. Regional Antarctic snow accumulation over the past 1000 years

56. Snow accumulation variability over the West Antarctic Ice Sheet since 1900: a comparison of ice core records with ERA-20C reanalysis

57. Blowing snow sublimation and transport over Antarctica from 11 years of CALIPSO observations

58. Heat flux distribution of Antarctica unveiled

59. Greenland Ice Sheet Surface Mass Loss: Recent Developments in Observation and Modeling

60. The modelled liquid water balance of the Greenland Ice Sheet

61. Algae drive enhanced darkening of bare ice on the Greenland ice sheet

62. The distribution and hydrological significance of rock glaciers in the Nepalese Himalaya

63. Simulated historical (1901–2010) changes in the permafrost extent and active layer thickness in the Northern Hemisphere

64. A new map of permafrost distribution on the Tibetan Plateau

65. Warmer spring conditions increase annual methane emissions from a boreal peat landscape with sporadic permafrost

66. Hemispheric asymmetry in stratospheric NO2 trends

67. A two-year forecast for a 60-80% chance of La Niña in 2017-18

68. How predictable are the Arctic and North Atlantic Oscillations? Exploring the Variability and Predictability of the Northern Hemisphere

69. Regime shift of Indian summer monsoon rainfall to a persistent arid state: external forcing versus internal variability

70. Inflated uncertainty in multi-model based regional climate projections

71. Climate and anthropogenic controls of coastal deoxygenation on interannual to centennial timescales

72. Changes in terrestrial near-surface wind speed and their possible causes: an overview

73. Uncertainty in recent near-surface wind speed trends: a global reanalysis intercomparison

74. A Statistical Study of Unusual Tracks of Tropical Cyclones near Taiwan Island

75. Severity scale for tornadoes

76. Variations of climate, surface energy budget and minimum snow/ice extent over Canadian Arctic landmass for 2000-2016

77. Intrinsic and atmospherically-forced variability of the AMOC: insights from a large ensemble ocean hindcast

Other papers

78. Social Resilience to Climate-Related Disasters in Ancient Societies: A Test of Two Hypotheses

"The paper finds that societies allowing greater political participation appear to provide greater resilience to catastrophic climate-related disasters, generally supporting the predominant perspective in contemporary disaster response."

79. The role of African dust in Atlantic climate during Heinrich events

80. Why artificial light at night should be a focus for global change research in the 21st century

An Inconvenient Sequel – the science, history, and politics of climate change

November 15, 2017 - 1:35am

Al Gore’s new movie ‘An Inconvenient Sequel’ is, in some ways, similar to his groundbreaking Inconvenient Truth project, but different in other ways. Those key differences are why I recommend you watch it.

This movie successfully accomplishes a number of interweaving tasks. First, it gives some of the science of climate change. Gore gets his science right. I remember his first movie, which I thought was more steeped in science and data than this one, so based on my recollection this new picture is somewhat abbreviated. That’s a good thing because the science is settled on climate change. That is, the science is settled that humans are causing current climatic changes and the science is settled that we are observing these changes throughout the natural world. 

Readers of this column who venture into the comments below will likely find people claiming, “science is never settled.” But the people making those comments are not scientists. They don’t work in this field every day, they don’t see the data, and they don’t know what they’re talking about.

The opening of the new film shows a sample of the misguided attacks on Al Gore, exclusively from conservatives in the United States. It was so clear to me, when watching and listening, that these attacks are the same ones that we climate scientists constantly have to endure. Most scientists have not been attacked as consistently or for such a long duration as Mr. Gore, but the types of attacks he has had to handle are close cousins to what my colleagues and I experience on a regular basis. 

Many conservatives, and some progressives too, claim that Al Gore made climate change political. But I now realize he didn’t. Al Gore was simply the first major political figure that took a stand on climate change. He would have loved to have been joined by anyone of any political persuasion. I firmly believe that the denialism we see from conservatives in the USA is partly because they cannot bring themselves to admit he was right. 

In many people’s subconscious, it is better to deny the science and damn the world than admit a liberal former vice president was correct. And that failure is on them. Better people would rise above gut emotions and follow facts faithfully to where they lead. Instead, most US conservatives have tied their legacy to a climate denial movement that is causing and will cause irreparable harm to the planet, its biology, and human societies.

A party that calls itself “conservative” has acted out of accord with its stated values. And this fact should anger true conservatives. How could they allow an entire party to be tarred with this damning legacy? It isn’t Mr. Gore’s fault that conservatives have made climate denial a litmus test for their party. It isn’t Gore’s fault that conservative politicians have been bought by fossil fuel industries who have attacked climate science and climate scientists. It isn’t Al Gore’s fault that the Republican Party has stood in the way of the development of clean renewable fuels in the US. That is on them. It isn’t Mr. Gore’s fault that the very few conservatives who have taken a principled stand have been cast out from their party. The politicization of science is their scar.

With respect to the science, this new movie focuses on actual implications of climate change. Whether Mr. Gore is discussing Greenland’s crumbling ice sheet with scientists Eric Rignot or Konrad Steffen, or conversing with Miami city planners on ways to handle rising waters, the movie brings the implications of a changing climate home. Mr. Gore reminds us of projections for the future. For instance, South Florida may see 7 feet of sea level rise by 2100. City planners are considering ways to raise parts of the city to deal with this. Oh by the way, yes the best evidence shows we really may get 7 feet by 2100.

Later, Gore meets with people who have suffered through terrible and super-charged storms, such as recent typhoons in the Pacific. He lays clear the science that climate change is warming our oceans, providing extra fuel to make storms like Irma, Harvey, Sandy, and Maria more powerful. In these spots, his science is dead on.

This may make you wonder why I recommend people watch this movie. Isn’t it just more doom and gloom? Well, this is the exciting part. While the politics of climate change, at least in the USA (with a President and Congress in full denial mode, not only rolling back progress but sabotaging the science), what reason is there to be hopeful?

First, other countries are taking the lead from the US. I see this in my own work. Not only in basic science but in deployment of renewable energy. This is one area of great potential. Even though, as shown in the movie, fossil fuel companies and some conservative politicians are trying to sabotage clean energy markets, they cannot deny the economics. It just makes sense to use clean and renewable energy.

Do you remember that iconic scene from his first movie, where he followed greenhouse gas data upward using a lift? The gas levels were literally off the screen? Well, that gloomy image is replaced in the new movie by an equally iconic but optimistic animation of how countries are installing clean energy. 

A large part of the story does deal with Al Gore’s personal journey.

Click here to read the rest

2017 SkS Weekly Climate Change & Global Warming News Roundup #45

November 11, 2017 - 11:55am
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week.  Editor's Pick

Conservatives probably can’t be persuaded on climate change. So now what?

One more round of “messaging” won’t do it.

 

When it comes to climate change, US conservatives inhabit a unique position, as part of the only major political party in the democratic world to reject the legitimacy of climate science and any domestic policy or international agreement meant to address it. Instead, the GOP is working actively to increase production and consumption of fossil fuels and to slow the transition to renewable energy.

How can conservatives be moved on climate change?

I recently heard a podcast that helped me order my thoughts on this perennial debate. It was Political Research Digest, a weekly 15-minute research round-up hosted by Michigan State University political scientist Matt Grossman for the Niskanen Center. (Grossman is the author of Asymmetric Politics, a crucial text for understanding American political parties. The podcast is nerdy and good.)

In the third episode, Grossman takes a look at some recent literature on climate change opinion and how, if at all, it can be shifted among conservatives.

It begins well, with an excellent lay of the land. But the discussion of how to move forward goes off course, in a very familiar way. It stops short of contemplating the uncomfortable but increasingly likely possibility that persuading conservatives on this subject has become impossible, and what that might mean for those concerned about the looming dangers of climate change.

Let’s start with a look a few basic facts about public opinion on climate.

Conservatives probably can’t be persuaded on climate change. So now what? by David Roberts, Energy & Environment, Vox, Nov 10, 2017  

Links posted on Facebook

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Wed Nov 8, 2017

Thu Nov 9, 2017

Fri Nov 10, 2017

Sat Nov 11, 2017

New research, October 30 - November 5, 2017

November 10, 2017 - 6:00am

A selection of new climate related research articles is shown below.

The graph is from paper #80.

Climate change

1. Observed warming over northern South America has an anthropogenic origin

"Results indicate that the recently observed warming in the dry seasons is well beyond the range of natural (internal) variability. In the wet season the natural modes of variability explain a substantial portion of Tmin and Tmax variability. We demonstrate that the large-scale component of greenhouse gas (GHG) forcing is detectable in dry-seasonal warming. However, none of the global and regional climate change projections reproduce the observed warming of up to 0.6 K/Decade in Tmax in 1983–2012 over northern SA during the austral spring (SON). Thus, besides the global manifestation of GHG forcing, other external drivers have an imprint."

2. Observed changes in temperature extremes over Asia and their attribution

"We determined that the warming trend was inconsistent with the natural variability of the climate system but agreed with climate responses to external forcing as simulated by the models. The anthropogenic and natural signals could be detected and separated from each other in the region for almost all indices, indicating the robustness of the warming signal as well as the attribution of warming to external causes."

3. Reduced cooling following future volcanic eruptions

"Using earth system model simulations we find that the eruption-induced cooling is significantly weaker in the future state. This is predominantly due to an increase in planetary albedo caused by increased tropospheric aerosol loading with a contribution from associated changes in cloud properties."

4. The 2015 drought in Washington State: a harbinger of things to come?

"In contrast to most historical droughts, which have been driven by precipitation deficits, our results suggest that 2015 is a useful analog of typical conditions in the Pacific Northwest by the mid-21st century."

5. Changes in intense tropical cyclone activity for the western North Pacific during the last decades derived from a regional climate model simulation

"Long-term trends (1948–2011 and 1959–2001) in both simulations show a strong increase of intense tropical cyclone activity. This contrasts with pronounced multidecadal variations found in observations."

6. Role of the North Atlantic Oscillation in decadal temperature trends

7. Intensified impact of North Atlantic Oscillation in May on subsequent July Asian inland plateau precipitation since the late 1970s

8. Teleconnection between Atlantic Multidecadal Variability and European temperature: diversity and evaluation of the CMIP5 models

9. Possible effect of the Tibetan Plateau on the “upstream” climate over West Asia, North Africa, South Europe and the North Atlantic

10. Impacts of Tropical North Atlantic SST on Western North Pacific Landfalling Tropical Cyclones

11. Extreme multi-basin flooding linked with extra-tropical cyclones

12. Synoptic Characteristics of Surge-Producing Extratropical Cyclones along the Northeast Coast of the United States

13. Global land surface temperature from the Along-Track Scanning Radiometers

14. In situ temperature measurements in the upper troposphere and lowermost stratosphere from 2 decades of IAGOS long-term routine observation

15. Characterizing transient temperature trajectories for assessing the value of achieving alternative temperature targets

16. Characteristics of a partially debris-covered glacier and its response to atmospheric warming in Mt. Tomor, Tien Shan, China

17. Assessment of climate change trends over the Loess Plateau in China from 1901 to 2100

18. The role of land surface fluxes in Saudi-KAU AGCM: Temperature climatology over the Arabian Peninsula for the period 1981–2010

19. Dark ice dynamics of the south-west Greenland Ice Sheet

20. Developments in Simulating and Parameterizing Interactions Between the Southern Ocean and the Antarctic Ice Sheet

21. Observationally constrained surface mass balance of Larsen C ice shelf, Antarctica

22. On the sensitivity of Antarctic sea ice model biases to atmospheric forcing uncertainties

23. Submesoscale Sea Ice-Ocean Interactions in Marginal Ice Zones

24. Analysis of the airflow at the centre of the upper plateau on the Iberian Peninsula and its link to CO2and CH4 concentrations

25. On the relationship between Atlantic Niño variability and ocean dynamics

26. Response of viticulture-related climatic indices and zoning to historical and future climate conditions in Greece

27. Systematic Errors in Weather and Climate Models: Nature, Origins, and Way Forward

28. Discrepancies in the climatology and trends of cloud cover in global and regional climate models for the Mediterranean region

29. Origin of the warm eastern tropical Atlantic SST bias in a climate model

30. Rainfall Characteristics of Recurving Tropical Cyclones Over the Western North Pacific

31. Investigation of Changes in Extreme Temperature and Humidity over China through a Dynamical Downscaling Approach

32. Satellite-retrieved direct radiative forcing of aerosols over North-East India and adjoining areas: climatology and impact assessment

33. Attribution and mitigation of heat wave-induced urban heat storage change

34. Increase in the skewness of extratropical vertical velocities with climate warming: fully nonlinear simulations versus moist baroclinic instability

35. Understanding, modeling and predicting weather and climate extremes: Challenges and opportunities

36. Spatial and temporal analysis of drought variability at several time scales in Syria during 1961–2012

37. Future changes in climate extremes over Equatorial East Africa based on CMIP5 multimodel ensemble

38. Comparison of the effect of land-sea thermal contrast on interdecadal variations in winter and summer blockings

39. Denitrification, dehydration and ozone loss during the 2015/2016 Arctic winter

40. What controls springtime fine dust variability in the western United States? Investigating the 2002-2015 increase in fine dust in the U.S. Southwest

Climate change impacts

41. Uncertain recovery of the North Atlantic right whale in a changing ocean

"Contrary to previous predictions, the right whale population is projected to recover in the future as long as prey availability and mortality rates remain within the ranges observed during 1980–2012. However, recent events indicate a northward range shift in right whale prey, potentially resulting in decreased prey availability and/or an expansion of right whale habitat into unprotected waters. An annual increase in the number of whale deaths comparable to that observed during the summer 2017 mass mortality event may cause a decline to extinction even under conditions of normal prey availability."

42. Extremely low genetic diversity across mangrove taxa reflects past sea level changes and hints at poor future responses

"We also used a recent series of flooding events in Yalong Bay, southern China, to test the robustness of mangroves to sea level changes in relation to their genetic diversity. The events resulted in the death of half of the mangrove trees in this area. Significantly, less genetically diverse mangrove species suffered much greater destruction. The dieback was accompanied by a drastic reduction in local invertebrate biodiversity. We thus predict that tropical coastal communities will be seriously endangered as the global sea level rises."

43. Observed long-term greening of alpine vegetation—a case study in the French Alps

"The timing of accelerated greening prior to 2000 coincided with a pronounced increase in the amount of snow-free growing degree-days that occurred during the 1980s and 1990s. In the case of grasslands and low-shrub habitats, we did not find evidence for a negative effect of grazing on greening trends, possibly due to the low grazing intensity typically found in the study area. We propose that the emergence of a longer and warmer growing season enabled high-elevation plant communities to produce more biomass, and also allowed for plant colonization of habitats previously characterized by long-lasting snow cover."

44. Vulnerability of Coral Reefs to Bioerosion From Land-Based Sources of Pollution

"Our results show that eutrophication of reef seawater by land-based sources of pollution can magnify the effects of OA through nutrient driven-bioerosion. These conditions could contribute to the collapse of coastal coral reef ecosystems sooner than current projections predict based only on ocean acidification."

45. Carbon dioxide and submersed macrophytes in lakes: linking functional ecology to community composition

46. Quantitative losses vs. qualitative stability of ectomycorrhizal community responses to 3 years of experimental summer drought in a beech-spruce forest

47. Assessing species climatic requirements beyond the realized niche: some lessons mainly from tree species distribution modelling

48. Latitude, temperature and habitat complexity predict predation pressure in eelgrass beds across the Northern Hemisphere

49. Glacial melt content of water use in the tropical Andes

50. Criminological Perspectives on Climate Change, Violence and Ecocide

51. Empowerment, climate change adaptation, and agricultural production: evidence from Niger

52. Predicting the outbreak of hand, foot, and mouth disease in Nanjing, China: a time-series model based on weather variability

53. Prioritizing coastal ecosystem stressors in the Northeast United States under increasing climate change

54. Might climate change the “healthy migrant” effect?

55. The Impact of Climate Change on Agriculture: Findings from Households in Vietnam

56. The suitability of Macadamia and Juglans for cultivation in Nepal: an assessment based on spatial probability modelling using climate scenarios and in situ data

57. Impact of climate variability on coffee yield in India—with a micro-level case study using long-term coffee yield data of humid tropical Kerala

58. Warming and top predator loss drive ecosystem multifunctionality

59. Climate mediates the success of migration strategies in a marine predator

60. Simulating the recent impacts of multiple biotic disturbances on forest carbon cycling across the United States

61. Vapor-pressure deficit and extreme climatic variables limit tree growth

62. Elevated carbon dioxide and warming impact silicon and phenolic-based defences differently in native and exotic grasses

63. Future riverine inorganic nitrogen load to the Baltic Sea from Sweden: An ensemble approach to assessing climate change effects

Climate change mitigation

64. Household installation of solar panels – Motives and barriers in a 10-year perspective

"Highlights

• Comparison of motives and barriers for installing photovoltaic panels in 2008 and 2014.
• Environmental motives have been consistent, financial incentives has been added.
• investment cost remained a barrier.
• New barriers increased administrative burden and finding information.
• Installation has disappeared as a barrier."

65. Evaluating the electricity intensity of evolving water supply mixes: the case of California's water network

"Electricity intensity (kWh m−3) will increase in arid regions of the state due to shifts to alternative water sources such as indirect potable water reuse, desalination, and water transfers. In wetter, typically less populated, regions, reduced water demand for electricity-intensive supplies will decrease the electricity intensity of the water supply mix, though total electricity consumption will increase due to urban population growth."

66. Slowing down the retreat of the Morteratsch glacier, Switzerland, by artificially produced summer snow: a feasibility study

"It takes about 10 years before snow deposition in the higher ablation zone starts to affect the position of the glacier snout. For the case of modest warming, the difference in glacier length between the snow and no-snow experiments becomes 400 to 500 m within two decades."

67. My neighbourhood, my country or my planet? The influence of multiple place attachments and climate change concern on social acceptance of energy infrastructure

68. Bayesian versus politically motivated reasoning in human perception of climate anomalies

69. Quantitative assessment of carbon sequestration reduction induced by disturbances in temperate Eurasian steppe

70. A Climate for Art: Enhancing Scientist-Citizen Collaboration In Bangladesh

71. Why the IPCC should evolve in response to the UNFCCC bottom-up strategy adopted in Paris? An opinion from the French Association for Disaster Risk Reduction

72. Public opinion and environmental policy output: a cross-national analysis of energy policies in Europe

73. The Relationships among Actual Weather Events, Perceived Unusual Weather, Media Use, and Global Warming Belief Certainty in China

74. Global consequences of afforestation and bioenergy cultivation on ecosystem service indicators

75. Impact of biofuels on contrail warming

Other papers

76. Spatial-temporal characteristics of aerosol loading over the Yangtze River Basin during 2001–2015

"There is no significant AOD trend over most areas of the Yangtze River Basin during 2001–2015, while strong decreasing trends are found over most of the middle and lower Yangtze Basin during 2011–2015. These decreasing trends may relate to changes in annual precipitation, wind speed, and air-pollution control policies."

77. North Atlantic influence on Holocene flooding in the southern Greater Caucasus

78. Quantifying the Release of Climate-Active Gases by Large Meteorite Impacts With a Case Study of Chicxulub

79. Is there 1.5-million-year-old ice near Dome C, Antarctica?

80. Reconstructing Northeastern United States temperatures using Atlantic white cedar tree rings

81. Designing the Climate Observing System of the Future

“Toasted, roasted and grilled” or already over the hump?

November 9, 2017 - 1:28am

Last week news stories came out that said that global human carbon emissions may have peaked, essentially implying that we could already be over the hump and on the way to solving climate change—while other news stories that same day and in that same publication noted that atmospheric carbon dioxide concentrations jumped by a record amount in 2016. These stories exemplify the emotional roller coaster that often comes with following climate change news. How can we reconcile the ebbs and flows between hopeful and apocalyptic climate stories?

The answer lies in considering the timeframe around a piece of climate news. For example, the seeming contradiction in the two news reports is explained by the monsterEl Niño event of 2016 that intensified droughts and consequently weakened the ability of vegetation to absorb carbon dioxide—showing that while human carbon pollution is responsible for the long-term rise in atmospheric concentrations, there is still ample short-term natural variation.

To give a second example: In a recent story, the managing director of the International Monetary Fund was quoted saying: “If we don't do anything about climate change now, in 50 years' time we will be toasted, roasted and grilled.” While that is an alarming statement, it focuses on a potential scenario in which half-a-century from now we have failed to change the course of our climate policies.

It’s important to remember, however, that with the international Paris climate accords, nearly every nation in the world agreed to begin the process to alter that worst-case course.

Another recent story noted that there’s a large gap between the Paris climate goals and the emissions cuts we’ve achieved so far. But the agreement was signed a mere two years ago, and global carbon emissions appear close to peaking. (They must peak by around 2020 to give us a realistic chance to meet the Paris targets). Moreover, it was agreed that countries must strengthen their emissions pledges during five-year reviews to meet the Paris goals, which means it’s hardly fair to pass judgment at this date. True, it’s too early yet to know if the world’s nations will indeed be able to follow through with such ambitious plans, but there are positive signs. For example, China had pledged to achieve peak carbon emissions by 2030, but it appears to already be approaching that goal 10-to-15 years ahead of schedule. That’s a significant development, so it bears repeating: China may reach its carbon reduction goals 10-to-15 years ahead of schedule.

On the other hand, the climate news coming out of the United States under the Trump administration seems constantly grim. However, the United States is just one country, and even there we see some good long-term news. Despite the administration’s efforts to maximize coal burning and the associated carbon pollution, coal is rapidly being phased out of the American power grid for purely economic reasons; quite simply, wind, solar, and natural gas are cheaper options.

Ultimately, the wildly fluctuating tone in climate change news stems from the fact that we now stand at a critical point in human history. To avoid causing exceptionally damaging climate changes, we must take aggressive steps now to cut human carbon pollution, and those actions must continually accelerate in the coming decades. The future climate will depend on the path we choose now and in the foreseeable future. Today’s scientists and journalists are trying to read the tea leaves to determine which path we’re taking, which leads to a see-sawing between "there’s hope" and "we’re doomed" stories.

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Rapid CO2 cuts could allow some cool-water corals to adapt to global warming

November 8, 2017 - 1:55am

This is a re-post from Carbon Brief by Daisy Dunne

Some of the world’s most diverse coral reefs are found in cooler parts of the tropics. These corals may be able to adapt to rising temperatures if future greenhouse gas emissions are drastically reduced, a new study suggests.

The modelling study simulates the effect of climate change on the survival of one population of a single coral species found off the coast of Rarotonga in the Cook Islands in the South Pacific. The researchers find that the genetic makeup of some cool-water corals might allow them to adapt to gradual increases in temperature.

However, without rapid cuts to emissions, the rate of climate change will likely outpace the ability of the corals to adapt, the study finds, resulting in the extinction of many coral populations by the end of the century.

More research will be needed to see if other cool-water corals around the world also hold the genetic code needed to adapt, another scientist tells Carbon Brief.

Fight for survival

Coral reefs make up some of the most ecologically important habitats in the world. Despite covering just 0.1% of the ocean floor, reefs help to support around 25% of marine species.

However, these diverse environments are vulnerable to climate change. This is because high sea temperatures causes coral bleaching, which is when corals expel the tiny colourful algae living in their tissues – known as zooxanthellae – leaving behind a stark white skeleton.

The algae provide the corals with energy through photosynthesis. Without them, the corals starve. Although corals can recover from a bleaching event, persistent bleaching can kill off entire reefs, leaving hundreds of thousands of marine species without a home.

But the new study, published in Science Advances, offers a glimmer of hope. It finds that this type of cool-water coral may be able to adapt to a rise in temperatures, if emissions are drastically cut in the coming decades.

For the study, the researchers concentrated their efforts on one population of a coral found in Rarotonga. The coral that lives here is called Acropora hyacinthus, which is a species considered to be “near threatened” by the International Union for the Conservation of Nature (IUCN).

In Rarotonga, corals live in relatively cool waters, says Dr Rachael Bay, lead author of the study from California State University. She tells Carbon Brief:

“It’s about 21 degrees south latitude which is towards the southern boundary of coral growth. So that population would be a considered a fairly cool reef, but then the question becomes, would that reef be able to adapt as temperatures warm up?”

Thermal tolerance

To find out if the corals could possibly evolve to adapt to climate change, the researchers first needed to assess whether the organisms possessed the right genetic material to allow them to cope with heat stress.

The researchers collected samples from 30 coral colonies across the island and used genetic techniques to scan the animals’ genomes, looking for specific variants of genes that are known to promote thermal tolerance in corals.

They found that a small proportion of corals living in Rarotonga do possess favourable variants of genes that convey tolerance to heat. This means that it is possible that, under the right conditions, the animals may be able to adapt to warming sea temperatures.

Model simulations

For the second part of the study, the researchers used computer simulations to estimate how quickly the corals could adapt to warming temperatures under a range of emissions scenarios. These included a relatively low emissions scenario (RCP2.6), an intermediate emissions scenario (RCP4.5), a moderately high emissions scenario (RCP6.0) and a high emissions scenario (RCP8.5).

You can read more about the four “RCPs”, or “Representative Concentration Pathways”, here. At present, global emissions are tracking closest to RCP8.5, the highest of the four.

The results show that coral populations simulated under RCP2.6 and RCP4.5 survive until 2100. However, under both RCP6.0 and RCP8.5, coral populations go extinct before the end of the century.

You can see this in chart B below, which shows the estimated coral population size from 2015 to 2100 under RCP2.6 (dark blue), RCP4.5 (light blue), RCP6.0 (orange) and RCP8.5 (red). The grey shows a scenario with no future warming. Chart A shows the estimated rise in the temperature of the hottest month from present until 2100 under each scenario.

A shows the estimated rise in temperature of the hottest month from present until 2100 under RCP2.6 (dark blue), RCP4.5 (light blue), RCP6.0 (orange) and RCP8.5 (red). B shows the estimated coral population size from 2015 to 2100 under each scenario. Source: Bay et al. (2017)

In the simulations under RCP2.6, the fraction of genetic variants conveying thermal tolerance steadily increases as temperatures rise. The rise suggests that heat-tolerant individuals are able to survive and reproduce, passing on their favourable genes to their offspring. So after an initial fall in coral population as temperatures rise, the simulations show the population recovering as the proportion of heat-tolerant individuals increases.

Under RCP4.5, coral populations do not initially adapt to the warming conditions, falling below 600 individuals between 2035 and 2065. At this point, only the most heat-tolerant individuals are able to survive. These individuals are able to reproduce and pass on their genes to their offspring, which led to a higher proportion of heat-tolerant corals, and a gradual recovery in the population.

But in simulations under both RCP6.0 and RCP8.5, the rate of warming is too fast for adaptation to take place. This is because heat-tolerant animals are likely to die before they have a chance to reproduce and pass on their genes to their offspring.

One location

Although the results suggest there is hope for some corals, the study only considers how climate change could affect one population at one location. Therefore, not all types of cool-water corals will be able to adapt in the same way, Bay cautions:

“While our results do specifically speak to one species in one location and that we certainly need further information on other species, people have found climate-associated genetic variation in other species, which means that they have potential to adapt. But we can’t really say without doing this kind of study how quickly that would happen.”

The research also highlights that there are important limits to adaptation, says Dr Mark Eakin, a coral specialist from the National Oceanic Atmospheric Administration(NOAA) and coordinator of NOAA’s Coral Reef Watch programme. He tells Carbon Brief:

“It’s clear that the corals are doing their part in trying to keep up with a warming ocean, but their survival requires that we all act quickly to not only stop – but also reverse – the excess CO2 we are dumping into the atmosphere. Unless we rapidly reduce global warming, corals won’t be able to adapt quickly enough to keep up.”

“More work is needed before we can generalise these results to the hundreds of coral species around the world.”

 

Bay, R. A. et al. (2017) Genomic models predict successful coral adaptation if future ocean warming rates are reduced, Science Advances http://advances.sciencemag.org/content/3/11/e1701413

What do Jellyfish teach us about climate change?

November 7, 2017 - 1:40am

What do Jellyfish teach us about climate change?

A lot. At least that’s what I learned after reading a very recent paper out in the journal Global Climate Change. The article, “Ocean acidification alters zooplankton communities and increases top-down pressure of a cubazoan predator,” was authored by an international team of scientists – the paper looks at impacts of climate change on life in the world’s oceans.

I recall attending a horse-pulling contest as a child. The announcer at the event said something strange that stuck with me all these years. He said that two horses pulling a load at the same time are more effective than if the two horses pulled separately and their loads were added. That is, something about two horses working together made them greater than the sum of their parts. This study is a lot like those horses.

To begin, ocean acidification refers to the changing pH of ocean waters. As humans emit more greenhouse gases (carbon dioxide in particular) into the atmosphere, the chemistry of the oceans change. The effect is that the creatures living in the oceans are experiencing an environmental change that is separate from changing temperatures due to global warming. Scientists want to know how these changes will affect creatures, in particular because the biodiversity in the oceans is so very important to us as humans.

There has been some reporting on studies of calcifying organisms and their susceptibility to changing chemistry in the oceans. For instance, echinoderms, molluscs, corals, and crustaceans have been studied in laboratories and in situ. The studies show that acidification reduces development and survival. Acidification can alter the way these creatures make and maintain their shells.

But the authors of this new study point out that there are many other non-calcifying organisms that may also be impacted by acidification. Even for these creatures, acidification has been shown to have deleterious effects that result in reduced survival, reduced reproductivity, and reduced size.

So how does ocean acidification affect these non-calcifying creatures? One hypothesis is that the new chemistry of the ocean changes these creatures’ metabolism. Upsetting the metabolism means they are less efficient at using caloric resources within their bodies. 

During this study, the authors utilized a very common zooplankton called calanoids. Calanoids make up approximately 80% of the zookplanton by mass. Consequently, they are very important. The authors also identified a predator of the calanoids - the “box jellyfish”. The fancy (scientific) word for box jellyfish is “cubozoa.” The authors wanted to know how changes to water pH affected the survival of the calanoids in the presence of a predator (the cubozoan). 

After bringing both creatures together into carefully designed tanks, the authors waited and watched. In some tanks, they just changed the ocean chemistry and did not introduce the predators. In other tanks, they introduced predators but kept the ocean chemistry fixed. In a third group of tanks, they both changed chemistry and introduced the predator. And then of course, they had control tanks with no chemistry changes or predators.

What they found was really interesting. While both changes to chemistry and introduction of predators affected the populations of calanoids, the simultaneous actions of acidification and predators was greater than the individual actions. So, we see the analogy with the horses.

Why are the combined effects of these two changes more potent? The authors give clues. If, for instance, a more acidic ocean reduces the metabolic efficiency of the creatures, then they will have less energy to escape predators. In fact, these calanoid creatures are known to escape predators by making a jump or a series of jumps. Consequently, in non-altered water, only about 1% of hunting tries are successful. But, in altered water, with less energy for the calanoids, perhaps more jellyfish hunts end in a meal. 

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2017 SkS Weekly Climate Change & Global Warming News Roundup #44

November 4, 2017 - 1:18pm
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week.  Editor's Pick

There’s a huge gap between the Paris climate change goals and reality

Current pledges are about a third of what’s needed.

 

Coal-fired power plant in Wyoming 

n 2015 in Paris, the countries of the world agreed to hold the rise in global average temperatures to “well below 2°C above pre-industrial levels and pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels.”

How’s that going?

The unavoidably grim answer: not well, and not just because President Donald Trump has promised to pull the United States out of the accord.

Every year, the United Nations Environment Program (UNEP) releases an “Emissions Gap” report, on the remaining disparity between the world’s stated ambitions on climate and the actions it is currently taking. The 2017 edition of the report is out a week before the next round of international climate talks in Bonn, Germany. And it reports that the gap remains ... substantial.

Researchers calculate that for a reasonable chance of hitting our goal, global greenhouse gas emissions must peak by 2020 and the gap must be closed by 2030 — in other words, if we are not on the right trajectory by 2030, all hope of 1.5 degrees is lost and 2 degrees is almost certainly out of reach as well.

Let’s run through a few of the top-line conclusions of the report, which was assembled by an international team of scientists based on the most recent published science. 

There’s a huge gap between the Paris climate change goals and reality by David Roberts, Energy & Environment, Vox, Oct 31, 2017

Links posted on Facebook

Sun Oct 29, 2017

Mon Oct 30, 2017

Tue Oct 31, 2017

Wed Nov 1, 2017

Thu Nov 2, 2017

Fri Nov 3, 2017

Sat Nov 4, 2017

New research, October 23-29, 2017

November 3, 2017 - 5:26am

A selection of new climate related research articles is shown below.

(Figure is from paper #16.)

Climate change mitigation

1. Geophysical potential for wind energy over the open oceans

"Wind speeds over open ocean areas are often higher than those in the windiest areas over land, which has motivated a quest to develop technologies that could harvest wind energy in deep water environments. However, it remains unclear whether these open ocean wind speeds are higher because of lack of surface drag or whether a greater downward transport of kinetic energy may be sustained in open ocean environments. Focusing on the North Atlantic region, we provide evidence that there is potential for greater downward transport of kinetic energy in the overlying atmosphere. As a result, wind power generation over some ocean areas can exceed power generation on land by a factor of three or more."

2. Public receptiveness of vertical axis wind turbines

"We find that the visual differences between the vertical and conventional wind turbines did not matter very much in any of the hypothetical settings in which we placed them. However, the prospect of killing fewer birds registered strongly with our survey respondents, though it could be outweighed by concern for cost. We also show that certain segments of the population, particularly those who are more educated, may be open to a more extensive deployment of vertical axis turbines in urban communities."

3. Getting the numbers right: revisiting woodfuel sustainability in the developing world

"The existing projects expect to produce offsets equivalent to ~138 MtCO2e. However, when we apply NRB values derived from spatially explicit woodfuel demand and supply imbalances in the region of each offset project, we find that emission reductions are between 57 and 81 MtCO2e: 41%–59% lower than expected."

4. Why people want to buy electric vehicle: An empirical study in first-tier cities of China

5. The Importance of Place in Communicating Climate Change to Different Facets of the American Public

6. Non-renewable and intermittent renewable energy sources: Friends and foes?

7. How do sectoral policies support climate compatible development? An empirical analysis focusing on southern Africa

8. Reflecting on a multidisciplinary collaboration to design a general education climate change course

9. Expansion of oil palm and other cash crops causes an increase of the land surface temperature in the Jambi province in Indonesia

10. Global Expansion of Renewable Energy Generation: An Analysis of Policy Instruments

11. What drives the GHG emission changes of the electric power industry in China? An empirical analysis using the Logarithmic Mean Divisia Index method

12. The comparative importance for optimal climate policy of discounting, inequalities and catastrophes

Climate change

13. Attributing changing rates of temperature record-breaking to anthropogenic influences

"The frequency of hot and cold record-breaking temperature occurrences is shown to be changing due to the anthropogenic influence on the climate. Using ensembles of model simulations with and without human-induced forcings, it is demonstrated that the effect of climate change on global record-breaking temperatures can be detected as far back as the 1930s. On local scales, a climate change signal is detected more recently at most locations. The anthropogenic influence on the increased occurrence of hot record-breaking temperatures is clearer than it is for the decreased occurrence of cold records."

14. Thirty-Three Years of Marine Benthic Warming Along the US Northeast Continental Shelf and Slope: Patterns, Drivers, and Ecological Consequences

"Benthic temperatures increased throughout the domain, including in the Gulf of Maine. Rates of benthic warming ranged from 0.1 to 0.4 °C per decade, with fastest rates occurring in shallow, nearshore regions and on Georges Bank, the latter exceeding rates observed in the surface. Rates of benthic warming were up to 1.6 times faster in winter than the rest of the year in many regions, with important implications for disease occurrence and energetics of overwintering species."

15. Trends in Extreme Rainfall Frequency in the Contiguous United States: Attribution to Climate Change and Climate Variability Modes

16. Investigating the local-scale influence of sea ice on Greenland surface melt

17. Modeling the response of Nioghalvfjerdsfjorden and Zachariae Isstrøm glaciers, Greenland, to ocean forcing over the next century

18. Influence of complex terrain and anthropogenic emissions on atmospheric CO2 patterns – a high-resolution numerical analysis

19. Future land use and land cover in Southern Amazonia and resulting greenhouse gas emissions from agricultural soils

20. Seasonal and diurnal variations in methane and carbon dioxide in the Kathmandu Valley in the foothills of the central Himalayas

21. Spatial and temporal variation in methane concentrations, fluxes, and sources in lakes in Arctic Alaska

22. Estimating solar radiation using NOAA/AVHRR and ground measurement data

23. Climate variability of heat wave and projection of warming scenario in Taiwan

24. Worsening of heat stress due to global warming in South Korea based on multi-RCM ensemble projections

25. Ensemble evaluation and projection of climate extremes in China using RMIP models

26. Regional Sea Level Variability and Trends, 1960–2007: A Comparison of Sea Level Reconstructions and Ocean Syntheses

27. Biogeochemical Impact of Snow Cover and Cyclonic Intrusions on the Winter Weddell Sea Ice Pack

28. Winter sea ice export from the Laptev Sea preconditions the local summer sea ice cover and fast ice decay

29. Glacier Calving in Greenland

30. Importance of positive cloud feedback for tropical Atlantic interhemispheric climate variability

31. The midsummer drought in Mexico: perspectives on duration and intensity from the CHIRPS precipitation database

32. Linking sea level rise and socioeconomic indicators under the Shared Socioeconomic Pathways

33. Predicting the patterns of change in spring onset and false springs in China during the twenty-first century

34. A 65-yr Climatology of Unusual Tracks of Tropical Cyclones in the Vicinity of China's Coastal Waters During 1949-2013

35. Atmospheric aerosol variability above the Paris Area during the 2015 heat wave - Comparison with the 2003 and 2006 heat waves

36. Climatic characteristics of heat waves under climate change: a case study of mid-latitudes, Iran

37. Definition of extreme El Niño and its impact on projected increase in extreme El Niño frequency

38. Using space lidar observations to decompose Longwave Cloud Radiative Effect variations over the last decade

Climate change impacts

39. The Future of Giant Clam-Dominated Lagoon Ecosystems Facing Climate Change

"The various documented cases support the hypothesis that mass mortalities of giant clams are triggered by climate variability, enhanced by the geomorphological specificities of these atolls. The exact mechanisms leading to mortalities and consequences for the whole ecosystem remain unknown and are probably case-dependent. These collapsing ecosystems represent well the fast impact that climate change can have on reef ecosystems."

40. Implications of Future Northwest Atlantic Bottom Temperatures on the American Lobster (Homarus Americanus) Fishery

"H. americanus experiences thermal stress at temperatures above 20°C, and projected increases in temperature is likely to result in changes in the distribution of optimal thermal egg hatching and settlement indicators. Inshore regions of southern New England, where H. americanus biomass and catch have been declining historically, will likely become inhospitable under either future scenario, while thermal egg hatching and settlement indicators will expand offshore and in the Gulf of Maine. These changes imply that members of the fishery based in southern New England may need to recapitalize to larger vessels to prepare for potential changes brought on by future climate warming."

41. Temporal changes in bird functional diversity across the United States

"We found increases in local bird species richness and taxonomic equitability that plateaued in the early 2000’s while total abundance declined over the whole period. Functional richness, the total range of traits in an assemblage, increased due to the rising prevalence of species with atypical life-history strategies and under-represented habitat or trophic preferences. However, these species did not trigger major changes in the functional composition of bird assemblages. Inter-annual variations in climate and primary productivity explained the richness of bird life-history traits in local assemblages, suggesting that these traits are influenced by broad-scale environmental factors, while others respond more to more local drivers."

42. Climate Change, the Economy, and Conflict

43. Understanding the Connections Between Climate Change and Conflict: Contributions From Geography and Political Ecology

44. Climate Change and Violence: Insights from Political Science

45. Environmental humanities and climate change: understanding humans geologically and other life forms ethically

46. Impact of climate change and seasonal trends on the fate of Arctic oil spills

47. Will Fluctuations in Salt Marsh - Mangrove Dominance Alter Vulnerability of a Subtropical Wetland to Sea-Level Rise?

48. Global-scale impacts of nitrogen deposition on tree carbon sequestration in tropical, temperate, and boreal forests: A meta-analysis

49. Growing at the Margins: Adaptation to Severe Weather in the Marginal Lands of the British Isles

50. Climate adaptation approaches and key policy characteristics: Cases from South Asia

51. Too weak to lead: motivation, agenda setting and constraints of local government to implement decentralized climate change adaptation policy in Ghana

52. Fail-safe and safe-to-fail adaptation: decision-making for urban flooding under climate change

53. Recent warming across the North Atlantic region may be contributing to an expansion in barley cultivation

54. Greater temperature and precipitation extremes intensify Western US droughts, wildfire severity, and Sierra Nevada tree mortality

55. What Is Currently Known About the Effects of Climate Change on the Coral Immune Response

56. Stand-level drivers most important in determining boreal forest response to climate change

57. Evidence for a climate-induced ecohydrological state shift in wetland ecosystems of the southern Prairie Pothole Region

58. Bird specimens track 135 years of atmospheric black carbon and environmental policy

59. Warming-induced upward migration of the alpine treeline in the Changbai Mountains, northeast China

60. Floating algae blooms in the East China Sea

61. Ambio special issue: Facets of Arctic Change

62. Future sea ice conditions and weather forecasts in the Arctic: Implications for Arctic shipping

63. Seafood from a changing Arctic

64. Animal responses to disturbance and climate extremes: Coping mechanisms in the new millennium

65. Is adaptation reducing vulnerability or redistributing it?

66. Quantifying the indirect impacts of climate on agriculture: an inter-method comparison

67. Climate change, fisheries management and fishing aptitude affecting spatial and temporal distributions of the Barents Sea cod fishery

68. Opposite effects of daytime and nighttime warming on top-down control of plant diversity

Other papers

69. Quantifying the influence of the terrestrial biosphere on glacial–interglacial climate dynamics

"On average across the period, the terrestrial biosphere has a −0.26 °C effect on temperature, with −0.58 °C at the Last Glacial Maximum. Depending on assumptions made about the destination of terrestrial carbon under ice sheets and where sea level has changed, the average terrestrial biosphere contribution over the last 120 kyr could be as much as −50 °C and −0.83 °C at the Last Glacial Maximum."

70. Holocene permafrost history and cryostratigraphy in the High-Arctic Adventdalen Valley, central Svalbard

71. Warming and Cooling: The Medieval Climate Anomaly in Africa and Arabia

72. Orbital signals in carbon isotopes: phase distortion as a signature of the carbon cycle

73. Predictability and non-Gaussian Characteristics of the North Atlantic Oscillation

Why people around the world fear climate change more than Americans do

November 2, 2017 - 1:47am

Gregory J. Carbone, Professor of Geography, University of South Carolina

This article was originally published on The Conversation. Read the original article.

When asked about major threats to their country, Europeans are more likely than Americans to cite global climate change, according to a recent Pew Research Center survey. Just 56 percent of Americans see climate change as a major threat, versus an average of 64 percent of Europeans surveyed.

Why the difference? Like climate data itself, data regarding public concern for climate change are “noisy.” Public response can vary depending on what’s going on in the news that week. Surveys of these types of surveys find no single explanation for how the public perceives the threat of climate change.

Of course, many explanations exist. As a climatologist who has taught university classes and given public lectures on global climate change for 30 years, I find it clear that public concern about climate change has evolved dramatically over the past three decades. In the U.S., now more than ever, it seems tied to ideology.

Knowing the facts

Does scientific literacy influence responses? Some psychologists think so. Indeed, some surveys show that Europeans have significantly greater scientific knowledge about the causes of climate change than Americans.

It’s possible that such knowledge translates into a sense of responsibility for mitigating climate change. But having more general scientific knowledge is not as relevant as knowing specifically about climate change.

A person’s outlook on the world can also complicate matters. Another recent Pew survey found that Americans are more likely to believe they control their own destiny and that they “tend to prioritize individual liberty, while Europeans tend to value the role of the state to ensure no one in society is in need.”

Research on the respective roles of scientific literacy and worldview reaches different conclusions. Psychologist Sophie Guy and colleagues argue that knowing the causes of climate change makes people more willing to accept the reality of climate change or to moderate their ideological opposition to it.

Nuisance flooding – flooding from ordinary high tides exacerbated by sea level rise and accompanying land subsidence – has increased 400 percent in Charleston, South Carolina since 1960. Stephen B. Morton/AP Photo

By contrast, Yale scholar Dan Kahan and colleagues find that people with the highest level of scientific literacy often use that literacy to retain and justify prior beliefs – what they call the “polarizing impact of science literacy.” In other words: “I’m smart, I’ve read the evidence and it confirms my prior understanding.” Climate change reflects a threat not only to one’s local environment, but also to one’s worldview.

Political affiliation

When you look more closely at recent survey responses in the U.S., the most striking and consistent finding is that political affiliation influences perceptions of climate change.

In the U.S., Democrats report, at consistently higher rates than Republicans, that climate change exists. Merely substituting the term “global warming” – now a politically charged catchword – for “climate change” makes the differences larger.

The divide between parties within the U.S. far exceeds the divide found between the U.S. as a whole and Europe. Political divisions also exist in Europe, and public opinion polls in the U.K. and Norway show that party similarly influences the perceived threat of climate change. However, there’s some evidence that the U.S. Republican Party is anomalous among conservative parties internationally. In other words, U.S. Republicans are more starkly anti-climate change than other conservative parties internationally.

It’s possible that the strong two-party system in the U.S. leads to a more binary mode of thinking on this issue that does not accurately represent that of the scientific community. Sociologist Aaron McCright and his colleagues argue that the high number of Americans identifying with the political right explains why the U.S., unlike other wealthy countries, is less concerned about climate change.

Closing the gap

Some suggest that the political divide has fueled an industry of climate change deniers and skeptics, distorting public perception about climate change science. Science historians Naomi Oreskes and Erik Conway argue in their book “Merchants of Doubt” that denial is about more than the science. It’s about political and economic systems that individuals hold dear. It also can result from differences in professional culture or personal values.

In the U.S., many of the most vocal skeptics and deniers of climate change emerge from conservative think tanks that revere the industrial capitalist system.

In Europe, differences between countries can also be explained by the voices of conservative think tanks and the media, but these voices are more influential in the U.S. than anywhere else because of the two-party system. Partisan clashes about climate change emerge from influential, well-funded sources that wield great influence on Congress, the media and ultimately the public. By contrast, most European countries have more than two parties, and arguably the political influence of corporations is lower.

Given the political divide on climate change in the U.S., addressing this 21st-century threat will require creative thinking that recognizes different worldviews and “beliefs” in climate change. The U.S. House Climate Solutions Caucus is a step in the right direction.

 

Greenhouse gas concentrations surge to new record

November 1, 2017 - 1:33am

via the WMO

Concentrations of carbon dioxide in the atmosphere surged at a record-breaking speed in 2016 to the highest level in 800 000 years, according to the World Meteorological Organization's Greenhouse Gas Bulletin. The abrupt changes in the atmosphere witnessed in the past 70 years are without precedent.

Globally averaged concentrations of CO2 reached 403.3 parts per million in 2016, up from 400.00 ppm in 2015 because of a combination of human activities and a strong El Niño event. Concentrations of CO2 are now 145% of pre-industrial (before 1750) levels, according to the Greenhouse Gas Bulletin.

 Rapidly increasing atmospheric levels of CO2 and other greenhouse gases have the potential to initiate unprecedented changes in climate systems, leading to “severe ecological and economic disruptions,” said the report.

The annual bulletin is based on observations from the WMO Global Atmosphere Watch Programme. These observations help to track the changing levels of greenhouse gases and serve as an early warning system for changes in these key atmospheric drivers of climate change.

Population growth, intensified agricultural practices, increases in land use and deforestation, industrialization and associated energy use from fossil fuel sources have all contributed to increases in concentrations of greenhouse gases in the atmosphere since the industrial era, beginning in 1750.

Since 1990, there has been a 40% increase in total radiative forcing – the warming effect on our climate - by all long-lived greenhouse gases, and a 2.5% increase from 2015 to 2016 alone, according to figures from the US National Oceanic and Atmospheric Administration quoted in the bulletin.

“Without rapid cuts in CO2 and other greenhouse gas emissions, we will be heading for dangerous temperature increases by the end of this century, well above the target set by the Paris climate change agreement,” said WMO Secretary-General Petteri Taalas. “Future generations will inherit a much more inhospitable planet, “ he said.

“CO2 remains in the atmosphere for hundreds of years and in the oceans for even longer. The laws of physics mean that we face a much hotter, more extreme climate in the future. There is currently no magic wand to remove this CO2 from the atmosphere,”said Mr Taalas.

The last time the Earth experienced a comparable concentration of CO2  was 3-5 million years ago, the temperature was 2-3°C warmer and sea level was 10-20 meters higher than now.

The WMO Greenhouse Gas Bulletin reports on atmospheric concentrations  of greenhouse gases. Emissions represent what goes into the atmosphere. Concentrations represent what remains in the atmosphere after the complex system of interactions between the atmosphere, biosphere, cryosphere and the oceans. About a quarter of the total emissions is taken up by the oceans and another quarter by the biosphere, reducing in this way the amount of CO2 in the atmosphere.

A separate Emissions Gap Report by UN Environment, to be released on 31 October, tracks the policy commitments made by countries to reduce greenhouse gas emissions and analyses how these policies will translate into emissions reductions through 2030, clearly outlining the emissions gap and what it would take to bridge it. 

"The numbers don't lie. We are still emitting far too much and this needs to be reversed. The last few years have seen enormous uptake of renewable energy, but we must now redouble our efforts to ensure these new low-carbon technologies are able to thrive. We have many of the solutions already to address this challenge. What we need now is global political will and a new sense of urgency," said Erik Solheim, head of UN Environment.

Together, the Greenhouse Gas Bulletin and Emissions Gap Report provide a  scientific base for decision-making at the UN climate change negotiations, which will be held from 7-17 November in Bonn, Germany.

WMO, UN Environment and other partners are working towards an Integrated Global Greenhouse Gas Information System to provide information that can help nations to track the progress toward implementation of their national emission pledges, improve national emission reporting and inform additional mitigation actions. This system builds on the long-term experience of WMO in greenhouse gas instrumental measurements and atmospheric modelling.

WMO is also striving to improve weather and climate services for the renewable energy sector and to support the Green Economy and sustainable development. To optimize the use of solar, wind and hydropower production, new types of weather, climate and hydrological services are needed.

Key findings of the Greenhouse Gas Bulletin Carbon dioxide

CO2  is by far the most important anthropogenic long-lived greenhouse gas. Globally averaged concentrations for CO2 reached 403.3 parts per million in 2016, up from 400.00 ppm in 2015. This record annual increase of 3.3 ppm was partly due to the strong 2015/2016 El Niño, which triggered droughts in tropical regions and reduced the capacity of “sinks” like forests, vegetation and the oceans to absorb CO2.   Concentrations of CO2 are now 145% of pre-industrial (before 1750) levels.

The rate of increase of atmospheric CO2 over the past 70 years is nearly 100 times larger than that at the end of the last ice age. As far as direct and proxy observations can tell, such abrupt changes in the atmospheric levels of CO2 have never before been seen.

Over the last 800 000 years, pre-industrial atmospheric CO2 content remained below 280 ppm, but it has now risen to the 2016 global average of 403.3 ppm.

From the most-recent high-resolution reconstructions from ice cores, it is possible to observe that changes in CO2 have never been as fast as in the past 150 years. The natural ice-age changes in CO2 have always preceded corresponding temperature changes. Geological records show that the current levels of CO2correspond to an “equilibrium” climate last observed in the mid-Pliocene (3–5 million years ago), a climate that was 2–3 °C warmer, where the Greenland and West Antarctic ice sheets melted and even some of the East Antarctic ice was lost, leading to sea levels that were 10–20 m higher than those today.

Methane

Methane (CH4) is the second most important long-lived greenhouse gas and contributes about 17% of radiative forcing. Approximately 40% of methane is emitted into the atmosphere by natural sources (e.g., wetlands and termites), and about 60% comes from human activities like cattle breeding, rice agriculture, fossil fuel exploitation, landfills and biomass burning.

Atmospheric methane reached a new high of about 1 853 parts per billion (ppb) in 2016 and is now 257% of the pre-industrial level.

Nitrous Oxide

Nitrous oxide (N2O) is emitted into the atmosphere from both natural (about 60%) and anthropogenic sources (approximately 40%), including oceans, soil, biomass burning, fertilizer use, and various industrial processes.

Its atmospheric concentration in 2016 was 328.9 parts per billion. This is 122% of pre-industrial levels. It also plays an important role in the destruction of the stratospheric ozone layer which protects us from the harmful ultraviolet rays of the sun. It accounts for about 6% of radiative forcing by long-lived greenhouse gases.

New data gives hope for meeting the Paris climate targets

October 30, 2017 - 1:45am

Over the past half-century, growth in the global economy and carbon pollution have been tied together. When the global economy has been strong, we’ve consumed more energy, which has translated into burning more fossil fuels and releasing more carbon pollution. But over the past four years, economic growth and carbon dioxide emissions have been decoupled. The global economy has continued to grow, while data from the EU Joint Research Centre shows carbon pollution has held fairly steady.

Annual global carbon dioxide and gross domestic product growth. Data from the EU Joint Research Centre and World Bank. Illustration: Dana Nuccitelli

China is becoming a global climate leader

China’s shift away from coal to clean energy has been largely responsible for this decoupling. Due to its large population (1.4 billion) – more than four times that of the USA (323 million) and nearly triple the EU (510 million) – and rapid growth in its economy and coal power supply, China has become the world’s largest net carbon polluter (though still less than half America’s per-person carbon emissions, and on par with those of Europeans). But as with the global total, China’s carbon pollution has flattened out since 2013.

 

That’s especially remarkable because it puts China about 15 years ahead of schedule. In an agreement with President Obama ahead of the Paris international climate negotiations, Chinese President Xi Jingping pledged that China’s carbon emissions would peak by 2030. Republican Party leaders grossly distorted this agreement at the time, with Senate majority leader Mitch McConnell claiming:

As I read the agreement it requires the Chinese to do nothing at all for 16 years while these carbon emissions regulations are creating havoc in my state and around the country

As the chart above shows, Chinese carbon emissions tripled between 1999 and 2013. To slow that rate of growth to zero as the Chinese economy continues to grow would require a dramatic shift in the country’s energy supply. But that’s exactly what’s happened, with the Chinese government cancelling over 100 planned new coal power plants earlier this year. Chinese coal consumption has in fact fallen since 2013. And China and the EU have pledged to strengthen their efforts to cut carbon pollution.

America isn’t a lost cause In 2016, American carbon pollution fell to below 1993 levels. The emissions decline began around 2008, which is also when natural gas, solar, and wind energy began rapidly replacing coal in the power grid.

The Trump administration has done everything in its power to reverse that trend. It began the withdrawal from the Paris climate agreement and the process to repeal the Clean Power Plan, has begun censoring EPA climate scientists and deleting climate change information from government websites, and proposed to prop up the dirty, failing coal industry with taxpayer-funded subsidies.

And yet, while these steps can slow the decline in American carbon pollution, the transition from coal to clean energy will nevertheless persist. Coal simply can no longer compete with cheaper, cleaner sources of energy, and the next American president can quickly reverse many of the Trump administration’s anti-climate orders.

Click here to read the rest

2017 SkS Weekly Climate Change & Global Warming News Roundup #43

October 28, 2017 - 12:44pm
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week.  Editor's Pick

Coal use must 'pretty much' be gone by 2050 to curb sea-level rise, researchers say

 

Warming waters are melting the Antarctic ice sheets from below. Photo: APT

Coal use will have to be "pretty much" gone by mid-century if the planet is to avoid sea-level rise of more than a metre by 2100 as Antarctic ice sheets disintegrate faster than expected, new modelling by an Australian-led team has found.

On business-as-usual projections, sea-level rise by the end of the century could exceed 1.3 metres compared with the 1986-2005 average, or 55 per cent more than predicted in the Fifth Assessment Report by the Intergovernmental Panel on Climate Change, according to research published in the Environmental Research Letters journal.

"We have provided a preview of what will have to be considered and assessed in more detail by the upcoming Sixth IPCC report," due for release in 2021, said Alexander Nauels, lead author of the report, and a researcher at Melbourne University's Australian-German Climate & Energy College. 

Coal use must 'pretty much' be gone by 2050 to curb sea-level rise, researchers say by Peter Hannam, Sydney Morning Herald, Oct 26, 2017

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Interpreting the Paris Agreement’s 1.5C temperature limit

October 27, 2017 - 1:35am

This is a re-post from Carbon Brief

Dr Joeri Rogelj is a research scholar at the International Institute for Applied Systems Analysis (IIASA) in Austria, and a coordinating lead author of the IPCC’s Special Report on 1.5CDr Carl-Friedrich Schleussner is head of climate science and impacts at Climate Analytics, and is on the steering committee of the initiative Half a degree Additional warming, Prognosis and Projected Impacts (HAPPI).

Long-term temperature limits like 2C or 1.5C above pre-industrial levels have long been used as goalposts for climate change mitigation.

Recently, these limits have received renewed attention in the scientific community, media and general public because of their inclusion in the Paris Agreement and the decision of the Intergovernmental Panel on Climate Change (IPCC) to prepare a Special Report on 1.5C.

However, the Paris Agreement itself does not spell out explicitly how such temperature limits should be used in climate policy and practice. These limits are therefore subject to interpretation, leading to confusion when trying to communicate how achievable the 1.5C limit is and the mitigation effort required.

In a commentary paper for the journal Geophysical Research Letters, we show that the temperature limits in the Paris Agreement should be understood as changes in long-term global averages attributed to human activity, which exclude natural variability.

This means 1.5C might be breached in individual years well before the global long-term 1.5C temperature limit has definitively been crossed.

Long-term goal

The long-term temperature goal agreed in Paris in December 2015 is enshrined in Article 2.1 of the final text. It outlines the aim to hold rising temperatures to “well below 2C above pre-industrial levels” while “pursuing efforts” towards the more ambitious limit of 1.5C.

The Paris Agreement final text. Source: UNFCCC (pdf)

The wording of the text is not without ambiguity (though this was arguably intentional in order to help reach agreement during negotiations). The agreement does not establish two “either-or” temperature goals, but a single goal, yet it does not make explicit how “well below 2C” or “limit to 1.5C” should be interpreted.

In the months since Paris there has been flurry of new journal papers and media articles focusing on the long-term goal – particularly the 1.5C limit – and this has highlighted the different ways in which it is being understood.

Much of the recent peer-reviewed research into 1.5C and 2C has taken the Paris Agreement temperature limits as long-term climatological global averages over multiple decades (see: herehere or here).

In others, the 1.5C and 2C limits have been compared to temperature metrics that look at smaller geographical scales or shorter time periods. These include, for example, looking at land temperatures only or at regional temperatures, or by assessing annual temperatures that include modes of natural variability such as the Pacific Interdecadal Oscillation.

Media articles have also discussed how close record monthly temperatures have come to hitting 1.5C above average.

These widely-different interpretations lead to quite different messages and insights, and have the potential to create confusion around what the long-term goal means and our chances of meeting the challenge.

Thought experiment

So, does it matter if the long-term goal is characterised in different ways? The simple answer is yes.

Widely-different interpretations lead to quite different messages and insights, and have the potential to create confusion around what the long-term goal means and our chances of meeting the challenge.

We illustrate this here with a thought experiment by showing how different warming limit interpretations affect the carbon budget for keeping to the 1.5C limit.

(We argue that one misinterpretation of international climate limits is to assume that they apply to global mean temperature rise including interannual natural variability. This is not the case – as will become clear further below – but let’s make this assumption for our thought experiment.)

Even in a stable climate, annual temperatures fluctuate around a long-term global temperature as a result of natural variability, caused by a range of unforced climate phenomena such as the El Niño-Southern Oscillation, and of variations in natural forcing, including volcanic eruptions, and variations in solar activity.

In a world where human-caused greenhouse gas emissions have taken long-term global warming to 1.5C, there would be a 50:50 chance of annual temperatures in any given year showing more than 1.5C of warming. In other words, you would expect to see more than 1.5C of warming one out of every two years on average over a sustained period of time.

Diverging interpretations of international warming limits, which look at exceeding 1.5C less frequently in individual years, make the challenge of keeping warming below 1.5C much greater.

In our thought experiment, we explore what happens when we reduce the chances of crossing 1.5C in any given year from one in two down to one in five, one in 10, one in 20, or never. The last of these levels, for example, means global temperature virtuallynever passes 1.5C of warming.

For this we derive annual average temperatures for each annual exceedance frequency using simulations from 24 climate models. You can see the results in the chart below, which shows the likely spread of annual temperatures as a result of natural variability.

So, for example, if we were to interpret the 1.5C limit as exceeding 1.5C of warming once every five years, we would actually need to hold the long-term global averagetemperature to 1.41C.

The more strictly we take the 1.5C goal, the lower the long-term average needs to be.

If we want to ensure annual global temperature never exceeds 1.5C of warming (see blue curve on the chart), we actually have to hold the long-term temperature to around 1C – a threshold we have almost reached.

Annual global average temperature anomalies from running a 21-year average for 24 climate models and the 1900-2090 period (combined historical and RCP2.6 scenario). Levels shown for four probabilities relating to the 1.5C limit, with the central bold line of each curve showing the equivalent average long-term temperature. Note: this is an approximation of natural variability, as it does not capture low frequency variability, and it also includes variations due to changes in historical natural solar and volcanic forcing. Credit: Joeri Rogelj.

Carbon budgets

Long-term temperature levels, such as those laid down in the Paris Agreement, provide guidance for short, mid and long-term global mitigation action.

One way they are used is by being translated into specific “carbon budgets” – this is the maximum amount of CO2 humans can emit while still having a good chance of meeting a given temperature limit.

Different interpretations of the long-term goal thus affect the carbon budget for 1.5C.

For example, if annual temperatures can only exceed a long-term temperature limit once every five years, the compatible carbon budget is around 200bn tonnes of CO2 smaller than the budget for once every two years. At current CO2 emission rates, that translates into using up the 1.5C budget around five years earlier.

For 1.5C never to be breached in any given year, the carbon budget would be reduced by more than 1,000bn tonnes of CO2.

This shows that there are substantial real-world policy differences involved in the interpretation of the Paris Agreement’s long-term temperature goal.

Our findings for each annual exceedance frequency are shown in the table below.

Implications of limits to the annual exceedance frequency of 1.5C for equivalent long-term global warming levels and respective carbon budgets, based on a transient climate response of 1.65C per 3664bn tonnes of CO2 (which is the average of the IPCC AR5’s likely 0.8 to 2.5C range). This estimate assumes invariable non-CO2 contributions. Reproduced from Rogelj et al. (2017). Note: the cumulative carbon budget for limiting warming to 1.5C relative to 1861-1880 in 50% of the model simulations was reported to be of the order of 2300bn tonnes of CO2 since 1870 in the IPCC Synthesis Report. A recent study, which has also been extensively covered on Carbon Brief and elsewhere online, reported updated estimates for an additional 0.6C of warming above the 2010-2019 average of about 730-880bn tonnes of CO2.

Legal and policy context

So, how can we know the correct way to interpret Paris Agreement temperature levels?

In our article, we show that the answer lies in analysis of the available information and examination of the context – in this case the legal framework of the United Nations Framework Convention on Climate Change (UNFCCC).

The United Nations Framework Convention on Climate Change (UNFCCC) – to which the Paris Agreement is a subsidiary legal instrument – defines “climate change” specifically as changes caused by human activity, without natural variability included.

UN Framework Convention on Climate Change (1992). Source: UNFCCC (pdf)

Further, the most recent IPCC assessment report provides additional clarity by defining “climate” as the statistical description in terms of the average and variability of relevant quantities over a period of time – with a classical period for averaging being 30 years, also commonly used by the World Meteorological Organisation (WMO).

In the context of the Paris Agreement, definitions set out by the UNFCCC will apply. In addition, IPCC assessment reports – particularly the most recent one – played a predominant role defining and underpinning the scientific components of the agreement.

Therefore, we argue that the long-term temperature goal in the Paris Agreement should be understood as long-term changes in climatological averages attributed to human activity – excluding natural variability.

Communicating 1.5C – the challenges ahead

Given the sensitive nature of the topic in the public debate, we think it is indispensable for the scientific community working on the topic to be well aware of the legal and scientific characteristics of the Paris Agreement long-term temperature goal.

At some point in the near future we will record the first year where the global average temperature is 1.5C warmer than pre-industrial levels. This will undoubtedly generate headlines.

Indeed, even before that, we will likely also see individual months and regions “exceeding” 1.5C.

But this won’t necessarily mean we’ve reached 1.5C of human-caused warming because a single month or year is also subject to natural variability. We need to be clear, for example, that even if a year sees 1.5C of warming, it need not mean that we have failed to fulfill the Paris Agreement – although it will provide an important warning shot.

While there are many challenges for scientists and policymakers in how we communicate climate change, being consistent about what the Paris Agreement temperature goal refers to should not be one of them. It is an essential step for providing relevant information to the public and policy debate alike.

New research, October 16-22, 2017

October 26, 2017 - 7:04am

A selection of new climate related research articles is shown below. Each week there are new research papers from all over the world. To illustrate this, the figure below shows the rough study locations of this week's papers (those who express their study location clearly in the abstract or in the title).

Climate change impacts

1. Drier climate shifts leaf morphology in Amazonian trees

"When accounting for such biases, our results indicate a trend of decreasing leaf size after the 1970s, which may have been spurred by an observed reduction in rainfall."

2. An Anthropological Perspective on the Climate Change and Violence Relationship

"Given that individuals make choices to respond violently or not based on their perceptions of these complex, interacting social and environmental conditions, violence in response to global climate change is not inevitable."

3. Rapid evolution of phenology during range expansion with recent climate change

"We found that in both common gardens, northern plants flowered up to four weeks earlier than southern plants. This differentiation in phenology extended from the core of the range to the Netherlands, a region only reached from central France over approximately the last 50 years. Fitness decreased as plants flowered later, supporting the hypothesized benefits of earlier flowering at the range edge. Our results suggest that native range expanding populations can rapidly adapt to novel environmental conditions in the expanded range, potentially promoting their ability to spread."

4. Influence of increasing temperature on the scorpion sting incidence by climatic regions

"Positive correlations among temperature and scorpion sting cases were found (R = 0.59 and 0.70 in the HR and WR, respectively). Regions with the hottest temperatures had the greatest effect, showing a 9.8% (CI 95%: 8.30–11.30) increase in scorpion sting cases per 1 °C increased in temperature. Increase in minimum and maximum temperatures have a delayed effect on scorpion stings cases and these may vary by climatic region."

5. How might recharge change under projected climate change in the western US?

"Overall, southern portions of the western US are expected to get less recharge in the future and northern portions will get more."

6. Tropical forests are thermally buffered despite intensive selective logging

"We therefore conclude that selectively logged forests are similar to primary forests in their potential for thermal buffering, and subsequent ability to retain temperature-sensitive species under climate change. Selectively logged forests can play a crucial role in the long-term maintenance of global biodiversity."

7. Influence of watershed topographic and socio-economic attributes on the climate sensitivity of global river water quality

8. Climate change responses among the Maasai Community in Kenya

9. The regulation of coralline algal physiology, an in situ study of Corallina officinalis (Corallinales, Rhodophyta)

10. Fire activity in Borneo driven by industrial land conversion and drought during El Niño periods, 1982–2010

11. The Eurasian hot nightlife: Environmental forces associated with nocturnality in lizards

12. Assessment of coastal governance for climate change adaptation in Kenya

13. Surface water CO2 concentration influences phytoplankton production but not community composition across boreal lakes

14. Thermal refugia against coral bleaching throughout the northern Red Sea

15. Potential benefits of drought and heat tolerance for adapting maize to climate change in tropical environments

16. A warmer and drier climate in the northern sagebrush biome does not promote cheatgrass invasion or change its response to fire

17. Poor plant performance under simulated climate change is linked to mycorrhizal responses in a semiarid shrubland

18. Glacier loss and hydro-social risks in the Peruvian Andes

19. Assessment of canola crop lodging under elevated temperatures for adaptation to climate change

20. Weather and eared grebe winter migration near the Great Salt Lake, Utah

21. Climate-smart agroforestry: Faidherbia albida trees buffer wheat against climatic extremes in the Central Rift Valley of Ethiopia

22. Pacific island regional preparedness for El Niño

23. Global and regional trends in particulate air pollution and attributable health burden over the past 50 years

24. Snow damage strongly reduces the strength of the carbon sink in a primary subtropical evergreen broadleaved forest

25. Data-constrained projections of methane fluxes in a Northern Minnesota Peatland in response to elevated CO2 and warming

26. A newly identified role of the deciduous forest floor in the timing of green-up

27. Are smallholder farmers’ perceptions of climate variability and change supported by climate records? A case study of Lower Gweru in semi-arid central Zimbabwe

28. Implications of climate change for the sugarcane industry

29. European butterfly populations vary in sensitivity to weather across their geographical ranges

30. Differential declines in Alaskan boreal forest vitality related to climate and competition

31. Simulating the onset of spring vegetation growth across the Northern Hemisphere

32. Uncertainty in climate change impacts on water resources

33. Global Climate Change Increases Risk of Crop Yield Losses and Food Insecurity in the Tropical Andes

Climate change mitigation

34. The effect of renewable and nonrenewable electricity generation on economic growth

"Our results indicate a strong positive and statistically significant relationship between renewable and nonrenewable electricity generation, and growth."

35. A nuclear- to-gas transition in South Korea: Is it environmentally friendly or economically viable?

"Highlights:

• Renewable energy can provide < 150 TWh of total electricity demand in South Korea.
• A gas transition will increase greenhouse-gas emissions in the electricity sector in South Korea.
• A gas transition will make the energy systems of South Korea vulnerable to external changes.
• A gas-focused energy future is being neither environmentally friendly nor economic.
The nuclear pathway offers the most viable policy for South Korea."

36. Economic and environmental costs of replacing nuclear fission with solar and wind energy in Sweden

"Replacing nuclear power with renewables in Sweden increases greenhouse-gas emissions."

37. Mobile measurement of methane emissions from natural gas developments in northeastern British Columbia, Canada

"Our results show that ~ 47 % of active wells were emitting. Abandoned and aging wells were also associated with emissions. We estimate methane emissions from this development are just over 111 Mt year−1, which is more than previous government estimates, but less than similar studies in the US."

38. Understanding stress effects of wind turbine noise – The integrated approach

39. Analysis of the relationship between local climate change mitigation actions and greenhouse gas emissions – Empirical insights

40. Fossil fuel subsidies in the Pacific island context: Analysis of the case of Kiribati

41. Investigating the rebound effect in road transport system: Empirical evidence from China

42. An assessment of individual foodprints attributed to diets and food waste in the United States

43. The moderating role of political affiliation in the link between flooding experience and preparedness to reduce energy use

44. Regional Climate Variability under Model Simulations of Solar Geoengineering

45. On the role of efficient cogeneration for meeting Mexico's clean energy goals

46. Co-benefits of integrating climate change adaptation and mitigation in the Canadian energy sector

47. Sustainability performance for Brazilian electricity power industry: An assessment integrating social, economic and environmental issues

48. Carbon sequestration by mangrove forest: One approach for managing carbon dioxide emission from coal-based power plant

49. Organic carbon storage change in China's urban landfills from 1978–2014

50. Investigating the multivariate Granger causality between energy consumption, economic growth and CO2 emissions in Ghana

51. Promoting green residential buildings: Residents' environmental attitude, subjective knowledge, and social trust matter

Climate change

52. Recent very hot summers in northern hemispheric land areas measured by wet bulb globe temperature will be the norm within 20 years

"We estimate that the likelihood of summer mean WGBT exceeding the observed historical record value has increased by a factor of at least 70 at regional scales due to anthropogenic influence on the climate. We further estimate that, in most northern hemispheric regions, these changes in the likelihood of extreme summer mean WBGT are roughly an order of magnitude larger than the corresponding changes in the likelihood of extreme hot summers as simply measured by surface air temperature. Projections of future summer mean WBGT under the RCP8.5 emissions scenario that are constrained by observations indicate that by 2030s at least 50% of the summers will have mean WBGT higher than the observed historical record value in all the analyzed regions, and that this frequency of occurrence will increase to 95% by mid-century."

53. The poleward shift of storm tracks under global warming: A Lagrangian perspective

"Our results imply that for a 4 K rise in the global mean surface temperature, the mean poleward displacement of cyclones increases by about 0.85° of latitude, and this occurs in addition to a poleward shift of about 0.6° in their mean genesis latitude. Changes in cyclone tracks may have a significant impact on midlatitude climate, especially in localized storm tracks such as the Atlantic and Pacific storm tracks, which may exhibit a more poleward deflected shape."

54. Quantification of temperature persistence over the Northern Hemisphere land-area

"For the mid-latitudes, we find that persistence in summer has increased over the past 60 years. The changes are particularly pronounced for prolonged events suggesting a lengthening in the duration of heat waves."

55. Light-absorbing impurities in a southern Tibetan Plateau glacier: Variations and potential impact on snow albedo and radiative forcing

56. Can we monitor snow properties on sea ice to investigate its role in tropospheric ozone depletion?

57. State-dependence of the Climate Sensitivity in Earth System Models of Intermediate Complexity

58. Southern Hemisphere bog persists as a strong carbon sink during droughts

59. Impacts of climate and land use on N2O and CH4 fluxes from tropical ecosystems in the Mt. Kilimanjaro region, Tanzania

60. Role of cloud feedback in regulating the “pool of inhibited cloudiness” over the Bay of Bengal

61. Role of Pacific trade winds in driving ocean temperatures during the recent slowdown and projections under a wind trend reversal

62. Interdecadal changes in winter surface air temperature over East Asia and their possible causes

63. Spatio-temporal pattern of meteorological droughts and its possible linkage with climate variability

64. Significance of aerosol radiative effect in energy balance control on global precipitation change

65. Changes in the East Asian summer monsoon rainfall under global warming: moisture budget decompositions and the sources of uncertainty

66. Changes in extreme precipitation in the Yangtze River basin and its association with global mean temperature and ENSO

67. Contribution of tropical cyclones to abnormal sea surface temperature warming in the yellow sea in december 2004

68. Delayed effect of Arctic stratospheric ozone on tropical rainfall

69. A satellite-derived climatology of unreported tornadoes in forested regions of northeast Europe

70. Numerical modeling of the active layer thickness and permafrost thermal state across Qinghai-Tibetan Plateau

71. Spatiotemporal changes in active layer thickness under contemporary and projected climate in the Northern Hemisphere

72. Australian snowpack in the NARCliM ensemble: evaluation, bias correction and future projections

73. Low-Frequency North Atlantic Climate Variability in the Community Earth System Model Large Ensemble

74. Attribution analysis of the Ethiopian drought of 2015

75. Global anthropogenic heat emissions from energy consumption, 1965–2100

76. Projected changes in mean rainfall and temperature over East Africa based on CMIP5 models

77. Evolving impacts of multi-year La Niña events on atmospheric circulation and US drought

78. Reconstructing the Western North Pacific Summer Monsoon since the late 19th century

79. Climatological Variability of Fire Weather in Australia

80. Dynamic downscaling over western Himalayas: Impact of cloud microphysics schemes

Other papers

81. A growing threat to the ozone layer from short-lived anthropogenic chlorocarbons

"We have observed large amounts of man-made chlorine compounds in E and SE Asia and in the upper tropical troposphere. These relatively short-lived compounds are not controlled by the Montreal Protocol, but if significant quantities were able to reach the stratosphere, the long-term recovery of stratospheric ozone would be delayed."

82. Reconciling differences in stratospheric ozone composites

"We find a significant ozone recovery since 1998 in the midlatitude upper stratosphere, with no hemispheric difference."

83. The Not-so Marginal Value of Weather Warning Systems

84. The spatial structure of the 128 ka Antarctic sea ice minimum

85. Temporal variability of the Charlotte (sub)urban heat island

What does a sexist Google engineer teach us about women in science?

October 25, 2017 - 4:29am

What does a sexist Google engineer teach us about women in science?

Nothing. 

That’s the short answer, but it deserves some commentary. In early August, a young Google computer engineer made lots of news in the US when he penned a manifesto that many described as sexist and which led to his firing. The memo was written as a backlash against efforts to improve diversity in the workplace. However, the arguments articulated by the manifesto were rightly described as offensive by Google executives. 

The explosive part in the memo involved comments about how biological differences explain the paucity of women in technology and leadership fields. While there are certainly both physical and mental differences between men and women, the comments about both genders are, in my opinion, misguided and offensive.

This article is not going to focus much on the content of this so-called manifesto. It also won’t focus on the author of this document, except to question the basis for how a very young engineer has the experience, training, or education to make such broad-brush generalizations. I mean, has he for instance managed scores of male and female engineers and been able to assess their quality of work and intellectual capacity? I doubt it. Has he studied this in any detail or published on the topic? I doubt it.

I found this manifesto so ironic because I give a lot of thought to differences between male and female scientists. I am not an expert in the area, certainly not in evolutionary biology. But I am a Full Professor with many years of instructing both undergraduate and graduate students in engineering. I am often struck by how small the female population is in my discipline (perhaps 20%), yet it is higher in other technical fields (biology, mathematics, chemistry, etc.). I am also impressed by how well female students do in technical courses and degree programs. I note a statistically significant performance gap between male and female students in courses; females consistently outperform their male peers.

I also have had the fortune to be a consultant for many different engineering companies from industries such as biomedical, aerospace, manufacturing, clean energy and other fields. In my work, I notice that women team members easily hold their own with male co-workers. I also believe (but I have no evidence) that women think differently than men. 

In my anecdotal experience, women are able to consider problems from a wider range of perspectives. This perspective has real value to design teams, it encourages companies to pay more for female employees (yes, our female engineering graduates tend to make more than their male counterparts). Diverse teams make effective teams. That includes gender diversity. So, in my 15 or so years as a professor, and in my perhaps 50 consulting positions, I have lived an experience very different from the one this young Google engineer articulated.

With all that said, I thought this event provided an excellent opportunity to showcase some female scientists who are either world-known or becoming world-known in the field of climate science. So, here are some short bios of brilliant women climate scientists.

Dr. Magdalena Balmaseda

Magdalena A. Balmaseda has been working at ECMWF since 1995. She currently leads the Earth System Predictability Section in the Research Department. 

Dr. Balmaseda has developed her career by helping us understand weather and climate. She has contributed to building bridges between the climate and weather sciences. Her expertise in ocean modelling in general, and in El Niño in particular, greatly contributed to ECMWF’s first steps in seasonal forecasting back in 1995. Now seasonal forecasts are one of the pillars of the EU Copernicus Climate Change Service (C3S), and the ocean is included in all ECMWF probabilistic forecasting systems, contributing the provision of forecasts of atmospheric conditions from days to months and seasons ahead. 

Equally important have been her contributions to the role of the ocean in a warming climate. The apparent slowing of the global rise in surface temperature in the first decade of the 21st century – the so-called “hiatus” – had puzzled the scientific community. In 2013 Dr. Balmaseda together with other colleagues demonstrated that a fair amount of energy trapped in the Earth system had actually been absorbed by deep ocean waters. This outcome was only possible thanks to a combination of information from ocean models, atmospheric winds, and ocean observations, using similar combination techniques as those employed for weather forecasting.

Dr. Karina von Schuckmann

Karina von Schuckmann is an oceanographer working in France at Mercator Ocean. She leads the ocean climate monitoring activities of the Copernicus Marine Environment Monitoring Service, which includes the development of a regular Ocean State Report with more than 100 authors. She is also a lead author of the upcoming Intergovernmental Panel on Climate Change Special report on ocean and cryosphere.

Her research is focused on the ocean’s role in the Earth energy budget. This means she studies how much heat is stored in and how it flows throughout the ocean waters. Her studies particularly highlight the unique importance of measuring the global ocean as its global heat storage is the most fundamental metric defining the status of global climate change and expectations for continued global warming. With this topic she is also playing a leading role on international scientific collaborations under the framework of the World Climate Research Program.

Dr. von Schuckmann’s résumé reads like a seasoned superstar’s; she has worked at some of the best research labs in France, the USA, Germany. I was so surprised to find she only recently received her PhD (in 2006). I want to know how she has become a leader in the field so quickly. I guess talent will do that. Her dissertation topic was on ocean climate variability in the tropical Atlantic Ocean. 

Dr. Jessica Conroy

Dr Jessica Conroy is a faculty member at the University of Illinois Urbana Champaign. She holds a dual appointment in the departments of Geology and Plant Biology. Another young and upcoming research scientist, she has been at the forefront of connecting modern climate observations and climate model outputs with long-past climate measurements (paleoclimate data). Her work has helped improve our understanding of past Earth climate.

In addition, she has developed long paleoclimate records from regions that are very sensitive to climate change. For instance, remote islands across the tropical Pacific and the Tibetan Plateau. She goes where few scientists have gone to make measurements that even fewer can.

Part of her work relies upon lake sediment samples and on the use of stable isotopes (oxygen and hydrogen) to give clues about what past climate was like. Not only does this give information about past temperatures but these data also, perhaps more importantly, tell us what the water cycle was like in the past. She was recently selected as a National Academy of Sciences Kavli Fellow. 

Dr. Sarah Myhre

Dr. Myhre is skilled in climate science as well as climate communication. Her area of research is in paleoceanography (the study of past climate and biology through the oceans). Her research requires her team to gather sediment cores from the seafloor, to analyze the chemical compositions and the shells of creatures that are contained within such cores, or to observe deep sea ecosystem using remotely operated submersibles. Her publications have appeared in some of the most prestigious scientific journals.

She may become even better known, however, for her work not only communicating about climate science to the general public but in training other scientists to be communicators. We scientists are often good at talking amongst ourselves, but we are less skilled at explaining why our research is important and how society can use our research to make informed decisions. This is where Dr. Myhre shines. She is a board member of the organization 500 Women Scientistsand the Center for Women and Democracy, and is an uncompromising advocate for women’s leadership in science and society.

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