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2018 SkS Weekly Climate Change & Global Warming News Roundup #16

April 21, 2018 - 1:05pm
A chronological listing of news articles posted on the Skeptical Science Facebook Page during the past week. Editor's Pick Earth Day and the Hockey Stick: A Singular Message 


Credit: Freestylephoto Getty Images

When the hockey stick was first attacked in the late 1990s I was initially reluctant to speak out, but I realized I had to defend myself against a cynical assault on my science and on me. I have come to embrace that role. What more noble cause is there than to fight to preserve our planet for our children and grandchildren?

There is great urgency to act now if we are to avert a dangerous 2- degree Celsius (3.6-degree Fahrenheit) planetary warming. My own recent work suggests the challenge is greater than previously thought. Yet I remain cautiously optimistic we will act in time. Along with many other Americans, I have been inspired by the renewed enthusiasm of our youth, who are demanding action now when it comes to the societal and environmental threats they face. Indeed, I have committed myself to helping insure a future in which we avoid catastrophic climate change. So let me conclude with this exhortation from the epilogue of The Hockey Stick and the Climate Wars:

“While slowly slipping away, that future is still within the realm of possibility. It is a matter of what path we choose to follow. I hope that my fellow scientists—and concerned individuals everywhere—will join me in the effort to make sure we follow the right one.” 

Earth Day and the Hockey Stick: A Singular Message, Opinion by Michael Mann, Observations, Scientific American, Apr 20, 2018

Links posted on Facebook

Sun Apr 15, 2018

Mon Apr 16, 2018

Tue Apr 17, 2018

Wed Apr 18, 2018

Thu Apr 19, 2018

Fri Apr 20, 2018

Sat Apr 21, 2018

New research, April 9-15, 2018

April 20, 2018 - 4:25pm

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

Climate change mitigation

1. Pathways limiting warming to 1.5°C: a tale of turning around in no time? (open access)

2. Climate change and technology: examining opinion formation of geoengineering

3. The Water-Energy-Food Nexus: A systematic review of methods for nexus assessment (open access)

4. What is the potential of cropland albedo management in the fight against global warming? A case study based on the use of cover crops (open access)

Emission reductions

5. Comparing nutritional, economic, and environmental performances of diets according to their levels of greenhouse gas emissions

"Diets with low GHGEs were characterized by a high nutritional quality. Primary energy consumption and land occupation increased with GHGEs (from Q1: 3978 MJ/year (95%CI = 3958–3997) to Q5: 8980 MJ/year (95%CI = 8924–9036)) and (from Q1: 1693 m2/year (95%CI = 1683–1702) to Q5: 7188 m2/year (95%CI = 7139–7238)), respectively. Finally, participants with lower GHGE related-diets were the highest organic food consumers. After adjustment for sex, age, and energy intake, monetary diet cost increased with GHGEs (from Q1: 6.89€/year (95%CI = 6.84–6.93) to Q5: 7.68€/year (95%CI = 7.62–7.74))."

6. Sustainability indicators in the swine industry of the Brazilian State of Santa Catarina

7. Will China's building sector participate in emission trading system? Insights from modelling an owner's optimal carbon reduction strategies

8. Can carbon pricing jointly promote climate change mitigation and human development in Peru?

9. Transition to low-carbon economy: Assessing cumulative impacts of individual behavioral changes (open access)

10. Steering transformations under climate change: capacities for transformative climate governance and the case of Rotterdam, the Netherlands (open access)

11. Annual emissions of CO2, CH4 and N2O from a temperate peat bog: Comparison of an undrained and four drained sites under permanent grass and arable crop rotations with cereals and potato

12. Carbon storage potential of cacao agroforestry systems of different age and management intensity

Energy production

13. Fukushima Through the Prism of Chernobyl: How Newspapers in Europe and Russia Used Past Nuclear Accidents

"The results show that the memory on the Chernobyl nuclear accident appeared in more than in every third article reporting of the present Fukushima nuclear accident despite the fact that Fukushima carried no direct radiological hazard for the newspaper’s audience and, a frequent use of narratives is related to negative attitudes towards nuclear energy, a higher risk perception of nuclear power plants and to an active nuclear energy industry in the newspaper’s country."

14. The Effects of Emergency Preparedness Communication on People’s Trust, Emotions, and Acceptance of a Nuclear Power Plant

15. Why homeowners strive for energy self-supply and how policy makers can influence them

16. The striking amount of carbon emissions by the construction stage of coal-fired power generation system in China

17. An integrated assessment of pathways for low-carbon development in Africa (open access)

18. Acceptance of wind energy and the role of financial and procedural participation: An investigation with focus groups and choice experiments

19. Could alternative energy sources in the transport sector decarbonise the economy without compromising economic growth?

20. Estimating temperature effects on the Italian electricity market

21. Measurement of natural and cyclical excess capacity in China's coal industry

22. Low-carbon energy generates public health savings in California (open access)

23. The rise and fall of foreign private investment in the jatropha biofuel value chain in Ghana

24. A greener gas grid: What are the options

25. Building or stumbling blocks? Assessing the performance of polycentric energy and climate governance networks

Climate change communication

26. Validating Conspiracy Beliefs and Effectively Communicating Scientific Consensus

"A central challenge to effectively communicating scientific consensus is that people often reject information counter to their prior beliefs. People who believe that human-induced climate change is a hoax, for instance, may dismiss scientific consensus messages that human activity is a primary cause of climate change. We argue that such people can be persuaded, however. We hypothesize that validating an individual’s belief about the existence of conspiracies makes him or her more likely to accept contrary scientific consensus information. We present experimental evidence that such validation leads individuals who previously believed human-induced climate change is a hoax to become more believing in human-induced climate change following exposure to scientific consensus information."

27. Correcting misinformation about climate change: the impact of partisanship in an experimental setting

"We find that corrections from Republicans speaking against their partisan interest are most likely to persuade respondents to acknowledge and agree with the scientific consensus on anthropogenic climate change. The extent of these effects vary by the partisanship of the recipient. Our results suggest that the partisan gap on climate change can be reduced by highlighting the views of elite Republicans who acknowledge the scientific consensus on anthropogenic climate change."

28. Overcoming barriers to climate change information management in small island developing states: lessons from pacific SIDS

29. Doom and gloom versus optimism: An assessment of ocean-related U.S. science journalism (2001-2015)

30. Conceptualizing climate vulnerability: Understanding the negotiating strategies of Small Island Developing States

Climate change

Temperature, precipitation, and wind

31. Interannual to decadal variability of the upper-ocean heat content in the western North Pacific and its relationship to oceanic and atmospheric variability

32. Northerly wind trends along the Portuguese marine coast since 1950

"Overall, the northerly wind intensity increased throughout the 1960s regardless of the area and dataset. Between 1960 and 2010, the northerly wind increased at a linear rate of 0.24, 0.09, and 0.15 m s-1 per decade in the NW, SW, and S coastal regions, respectively. The rate was higher in recent decades (1988–2009), with the wind intensity increasing by 0.4, 0.3, and 0.3 ms-1 per decade in the NW, SW, and S regions, respectively."

33. Intercomparison of Surface Temperatures from AIRS, MERRA, and MERRA-2, with NOAA and GC-Net Weather Stations at Summit, Greenland

34. Precipitation regimes over central Greenland inferred from 5 years of ICECAPS observations (open access)

35. Hierarchical Bayesian space-time estimation of monthly maximum and minimum surface air temperature

36. Impacts of half a degree additional warming on the Asian summer monsoon rainfall characteristics (open access)

Extreme events

37. Climate change and the global pattern of moraine-dammed glacial lake outburst floods (open access)

"We have produced the first global inventory of GLOFs associated with the failure of moraine dams and show, counterintuitively, that these have reduced in frequency over recent decades."

38. Geo-anthropogenic aberrations and Chennai floods: 2015, India

39. Tropical storm Chedza and associated floods over south-eastern Africa

Forcings and feedbacks

40. Constraints on global oceanic emissions of N2O from observations and models (open access)

41. Continued increase of CFC-113a (CCl3CF3) mixing ratios in the global atmosphere: emissions, occurrence and potential sources (open access)

"The continued presence of northern hemispheric emissions of CFC-113a is confirmed by our measurements of a persistent interhemispheric gradient in its mixing ratios, with higher mixing ratios in the Northern Hemisphere. The sources of CFC-113a are still unclear, but we present evidence that indicates large emissions in East Asia, most likely due to its use as a chemical involved in the production of hydrofluorocarbons."

42. The Network for the Detection of Atmospheric Composition Change (NDACC): history, status and perspectives (open access)

43. Long-term record of top-of-atmosphere albedo over land generated from AVHRR data

44. Concentrations and source regions of light-absorbing particles in snow/ice in northern Pakistan and their impact on snow albedo (open access)

45. Improving the simulation of tropical convective cloud top heights in CAM5 with CloudSat observations


46. Future projections of Antarctic ice shelf melting based on CMIP5 scenarios

"Every sector of Antarctica shows increased basal melting in every scenario, with the largest increases occurring in the Amundsen Sea. The main mechanism driving this melting is an increase in warm Circumpolar Deep Water on the Antarctic continental shelf."

47. Multi-year analysis of distributed glacier mass balance modelling and equilibrium line altitude on King George Island, Antarctic Peninsula (open access)

48. Changing pattern of ice flow and mass balance for glaciers discharging into the Larsen A and B embayments, Antarctic Peninsula, 2011 to 2016 (open access)

49. Recent dynamic changes on Fleming Glacier after the disintegration of Wordie Ice Shelf, Antarctic Peninsula (open access)

"Fleming Glacier is the biggest tributary glacier of the former Wordie Ice Shelf. Radar satellite data and airborne ice elevation measurements show that the glacier accelerated by ~27 % between 2008–2011 and that ice thinning increased by ~70 %. This was likely a response to a two-phase ungrounding of the glacier tongue between 2008 and 2011, which was mainly triggered by increased basal melt during two strong upwelling events of warm circumpolar deep water."

50. Glacier mass budget and climate reanalysis data indicate a climatic shift around 2000 in Lahaul-Spiti, western Himalaya

51. Thermodynamic and dynamic ice thickness contributions in the Canadian Arctic Archipelago in NEMO-LIM2 numerical simulations (open access)

52. The strengthening relationship between Eurasian snow cover and December haze days in central North China after the mid-1990s (open access)

53. Historical and future changes of snowfall events in China under a warming background

54. Estimating the snow water equivalent on a glacierized high elevation site (Forni Glacier, Italy) (open access)

55. Multi-component ensembles of future meteorological and natural snow conditions for 1500 m altitude in the Chartreuse mountain range, Northern French Alps (open access)


56. Trend analysis of hydro-climatic variables in the north of Iran

57. Climate model assessment of changes in winter-spring streamflow timing over North America

Carbon cycle

58. Dependence of the evolution of carbon dynamics in the northern permafrost region on the trajectory of climate change

"Our analysis indicates that the northern permafrost region could act as a net sink for carbon under more aggressive climate change mitigation pathways. Under less aggressive pathways, the region would likely act as a source of soil carbon to the atmosphere, but substantial net losses would not occur until after 2100."

59. High-frequency productivity estimates for a lake from free-water CO2 concentration measurements (open access)

60. Phenological mismatch in coastal western Alaska may increase summer season greenhouse gas uptake (open access)

61. Carbon fluxes and interannual drivers in a temperate forest ecosystem assessed through comparison of top-down and bottom-up approaches

62. Estimates of CO2 fluxes over the city of Cape Town, South Africa, through Bayesian inverse modelling (open access)

Atmospheric and oceanic circulation

63. Evaluation of performance of CMIP5 models in simulating the North Pacific Oscillation and El Niño Modoki

64. Mechanisms and Predictability of Pacific Decadal Variability

Climate change impacts


65. Intercropping of coffee with the palm tree, macauba, can mitigate climate change effects

"Compared with the traditional unshaded sole coffee planting, the intercropped cultivation provided more coffee yield on both macauba density planting and distance evaluated. On the other hand, coffee productivity was increased by agroforestry systems just for 4.2 m distance between palm trees and coffee rows. Planting density of macaubas did not affect coffee yield and productivity. Best coffee harvest in agroforestry systems with macauba was related to higher soil moisture at the depth of 20–40 cm, higher photosynthetic active radiation, and maximum air temperatures lower than 30 °C."

66. Climate change adaptation: a study of multiple climate-smart practices in the Nile Basin of Ethiopia

67. Community-based adaptation in low-lying islands in the Philippines: challenges and lessons learned

68. Improving the representation of adaptation in climate change impact models (open access)

69. Collaboration between meso-level institutions and communities to facilitate climate change adaptation in Ghana

70. Effects of drought and flood on crop production in China across 1949–2015: spatial heterogeneity analysis with Bayesian hierarchical modeling

71. Uncertain impacts on economic growth when stabilizing global temperatures at 1.5°C or 2°C warming (open access)


72. Enhanced canopy growth precedes senescence in 2005 and 2010 Amazonian droughts

73. Drought sensitivity and stem growth variation of nine alien and native tree species on a productive forest site in Germany

74. Machine learning modeling of plant phenology based on coupling satellite and gridded meteorological dataset

Other impacts

75. Isoprene emission response to drought and the impact on global atmospheric chemistry

Other papers

General climate science

76. The color of melt ponds on Arctic sea ice (open access)


77. The sensitivity of the Greenland Ice Sheet to glacial–interglacial oceanic forcing (open access)

Environmental issues

78. The effects of air pollution on daily cardiovascular diseases hospital admissions in Wuhan from 2013 to 2015

79. A national-scale review of air pollutant concentrations measured in the U.S. near-road monitoring network during 2014 and 2015

Glacier loss is accelerating because of global warming

April 18, 2018 - 1:32am

With global warming, we can make predictions and then take measurements to test those predictions. One prediction (a pretty obvious one) is that a warmer world will have less snow and ice. In particular, areas that have year-round ice and snow will start to melt.

Alpine glaciers are large bodies of ice that can be formed high in mountains, typically in bowls called cirques. The ice slowly flows downwards, pulled by gravity, and is renewed in their upper regions. A sort of balance can occur where the loss of ice by melting or flowing at the bottom is equal to the gain of snow and ice by precipitation.

As the Earth warms, the melt line moves upwards so that the glacier melts faster and faster at the bottom, shortening the glacier and reducing its mass. Ultimately, the melted water flows into streams and rivers and ends up in the oceans, contributing to accelerating sea level rise.

While glaciers are interesting from an intellectual standpoint, they are also important to ecosystems and society. For example, the rate of glacier melt affects downstream water levels, river flowrates, and the water available for human use. So, it would be really important for us to be able to predict what will happen with glaciers in the future and plan for how water availability will change.

Of the groups that track glaciers, my favorite is the World Glacier Monitoring Service, which publishes a survey of the mass changes from selected glaciers around the world, available here and summarized below. The graph shows changes to the mass of the glaciers that are monitored, measured in millimeters of equivalent water.

Changes to water content of glaciers. Illustration: World Glacier Monitoring Service

But this doesn’t tell the whole story because there is very little information about glacier health in the high latitudes (Northern Alaska, Canada, Northern Europe, Northern Russia, etc.). Very few temperature records exist in high elevations in these regions. Furthermore, the temperatures do not extend back very far in time. So, it is challenging for scientists to develop a long-term perspective on glacier health in these areas.

And this is why a new study attracted my attention. A paper was just published by the American Geophysical Union that shared research carried out by Dominic Winski and his colleagues.

This team of researchers extracted ice cores from the glaciers on Mt. Hunter, in Alaska. The ice cores held snow and ice from as far back as 400 years. The researchers showed that the amount of water melt currently is 60 times greater than it was prior to 1850. They also found that the summertime temperature changes on Mt. Hunter are almost 2°C per century (about 3.5°F). To put this in perspective, the temperatures are rising about twice as fast as global temperatures.

Click here to read the rest

Climate Science Denial Explained: Tactics of Denial

April 17, 2018 - 1:42pm

Continued from Part 1

What they decline to understand

Thousands of climate scientists are working on all kinds of interesting subjects, from glaciology to oceanography to ecology to atmospheric physics. Some pseudo-skeptics don't understand that and seem to have no inkling of what climate scientists actually do.

Others, however, do understand that there's a large and sometimes-maybe-legitimate scientific endeavor going on, and they are happy to learn about some of that stuff, as long as they don't have to accept that human emissions cause warming.

While the land (red) has warmed faster than the ocean surface (blue), sea surface temperatures have the most impact on the global average because oceans cover 71% of earth’s surface. If global warming were caused by internal variability in the oceans (in other words, if the ocean surface warmed up because less cold deep water were being exchanged with it), then sea surfaces should warm as fast as the land. And if global warming were caused by the sun, days would warm faster than nights; in fact the opposite is true. Besides, solar output is measurable and has been decreasing. It is likely that warming in the 1920s and 1930s was caused largely by internal variability, and cooling in the 1950s, 60s and 70s has been attributed largely to internal variability plus aerosol emissions that happened before environmental regulations were introduced to reduce smog. Unlike CO2, aerosols disappear quickly from the atmosphere when emissions stop. So as our air got cleaner, the effect of CO2 became dominant.

Other things they're reluctant to accept include "global warming is dangerous" and "the problem can be solved" (and if you ask me, it isn't even that hard anymore).

The 5 characteristics

Whether the topic is climate change, lung cancer’s link to smoking, vaccines & autism, AIDS or MSG, denial of scientific findings relies on a set of techniques that can be summed up by the acronym FLICC:

Fake experts: climate science is huge and complex field, as you can see from IPCC reports that need 4,000 pages merely to summarize the state of the field. No expert knows everything about it, as the field has numerous specializations. While many articles on denial blogs are written by “scientists” (such as computer scientists or geologists), most articles are not written by contrarian climate scientists, and contrarians themselves are not experts in most of the subspecialties they criticize. Pseudo-skeptics trust people with little or no credentials in the field, and may even think they themselves are experts after reading a pseudo-skeptic book or two. So when TV networks put Bill Nye on the screen to face off against an AGW pseudo-skeptic, other pseudo-skeptics may point out that Bill Nye is not a climate scientist — while cheering on the other guy, who is not a climate scientist either.

Magnified Minority: Though 3% of experienced climate scientists disagree with the consensus, media often give pseudo-skeptics 50% screen time. There is another small minority of scientists, and perhaps the occasional climatologist, who believe there will be much more warming than typically thought — we might call these “alarmists”. But some media treats the consensus position itself as “alarmist”, so instead of pitting “contrarians” against “alarmists”, it’s “contrarians” versus “mainstream scientists whom we call alarmists to discredit them”.

Logical fallacies: Most pseudo-skeptic beliefs are based on logical errors and/or an absence of knowledge and context. Most myths about climate change can be described in terms of a few fallacies (see below).

Impossible expectations: demanding more precision and more perfect information than climate science can realistically deliver. For example, J.S. Sawyer estimated in 1972 that by the year 2000, atmospheric CO2 levels would rise about 25% compared to 1969 and that global temperatures would rise 0.6°C. Temperatures did in fact rise slightly more than 0.6°C by the time CO2 rose 25%, but it took until after 2010 for this to happen; I assume this is because early estimates of the rate at which carbon sinks (oceans and vegetation) absorb CO2 were too low. Most people would see this as a remarkably accurate prediction, especially since the temperature record in 1972 showed no hints that temperatures were about to rise. Pseudo-skeptics, however, seize upon the imperfection of the prediction as ‘another example’ of why we can’t trust climate science. Similarly, the 1995 IPCC projections (unlike the 1990 and 2000 ones) substantially underestimated the amount of warming that would occur by 2016. Upon learning this, a pseudo-skeptic I spoke with saw it as more evidence of bad science. (“so you’d disagree with anyone who calls the IPCC alarmist?” I asked. “Alarmists don’t underestimate.” He ignored the question.)

Cherry picking: cherry picking is another logical fallacy, but pseudo-skeptics tend to use it far more than the others. For example, the pseudo-skeptic says correctly that the antarctic is gaining sea ice, that one study (controversially) says it’s gaining land ice, and that specific parts of Greenland are gaining ice. But they avoid the bigger picture: the water around Antarctica has warmed up, it may be losing land ice, the arctic is quickly losing ice, Greenland as a whole has been losing ice at an accelerating pace for about 13 years, and far more glaciers are losing ice than gaining ice. They also cherry-pick predictions from individualclimatologists that turned out to be inaccurate, while ignoring predictions from contrarians that were more wrong (past contrarians predicted imminent cooling. Since that didn’t happen, remaining contrarians tend to imply it’s impossible to predict climate — a concept that will allow denial to continue forever, no matter what happens).

Conspiracy theories: last but not least, pseudo-skeptics need a way to explain why most climate scientists came to the “wrong” conclusion, so conspiratorial thinking fills in the blanks. I’ve seen claims of conspiracy or corruption many times, but always with a striking lack of detail. I’ve never encountered a complete story: why it happened, when it happened, who did it (specific people), and how it was pulled off. The best they can do is misunderstand a handful of leaked emails. This makes sense if the idea of conspiracy, or corruption, or a vast global network of incompetent scientists, is all just a backdrop — a curtain hastily installed to cover up the consensus so it can be ignored. But there is another interpretation for this lack of detail. Perhaps the idea of conspiracy or corruption is actually the primary belief held by most pseudo-skeptics, but because there is so little direct evidence for it, pseudo-skeptics are forced to rely on indirect evidence in the form of scientific findings that are “flawed” according to black-belts in FLICC-fu.

“Conspiracy theories turn out to be unusually hard to undermine or dislodge; they have a self-sealing quality, rendering them particularly immune to challenge.” - Conspiracy Theories: Causes and Cures “the more participants believed that Princess Diana faked her own death, the more they believed that she was murdered” - Dead and Alive … Contradictory Conspiracy Theories

Here are the main logical fallacies:

  • Red Herring: a minor detail used to mislead or derail a discussion. You can hear them nitpicking the title of this article already: “I don’t deny that climate changes, I deny human responsibility!” Yes, but a more pedantic headline would be too long. Similarly, pseudo-skeptics may point out that CO2 is a “trace” gas (less than 0.1% atmospheric concentration). They can admit that all plant life would die without CO2, yet claim that a trace gas can’t possibly have a noticeable effect on climate. This is a red herring and an example of the “argument from incredulity”. Of course, there are many examples of small things making a clear difference: microscopic windshield coatings to reduce glare, tiny pits that increase airplane fuel efficiency, fluoride in water. Another example: CO2 dissolved in water is carbonic acid, and causes the ocean’s pH to fall toward the “acid” side of the pH scale. We call this “ocean acidification”. However, ocean water is on the alkaline (non-acid) side of the pH scale, so pseudo-skeptics distract by questioning the intellect of people who use the word “acidification”. In short, if sea horses start dying, it’s okay because they’re not really horses!
  • Misrepresentation (straw man or half-truth): misstating scientific predictions or findings. For example, pseudo-skeptics may misrepresent the 2nd law of thermodynamics to “prove” that the greenhouse effect can’t be real. Or they pretend that scientists are certain about precisely how much warming CO2 will cause, and then attack a certainty that doesn’t exist. Or they misrepresent how scientists reached their conclusions, to demonstrate a “circular reasoning” that doesn’t exist. Or they quote an erroneous news article that misstated a scientific prediction. They might even find a prediction that says “by 2050” and call it “failed” because it hasn’t happened yet. The list goes on and on.
  • Jumping to conclusions: when you really want something to be true, it’s easy to ignore details that contradict your conclusion. For instance, the urban heat island effect may raise some temperature readings due to urbanization. Also, satellite records interpreted by UAH show less warming than other records. So they jump to the conclusion that warming has been small. However, almost the same warming can be seen based on rural temperature stations and rural records alone; and weather balloons and high-resolution proxy records also show similar warming. In fact, ocean records are the main factor in global average temperatures, since they make up 71% of Earth’s surface. As for satellites, the same satellite records interpreted by RSS show significantly more warming than UAH. Why? Satellites don’t measure temperature, and the data is very tricky to interpret. Satellites show day-to-day differences reliably, but the readings drift in multiple ways as years and decades pass. Both UAH and RSS have repeatedly changed how they compensate for drift, which in turn changed their temperature trends retroactively.
  • False dichotomy: incorrectly assuming there are only two possibilities, then showing one of the possibilities is wrong to “prove” the other. The most common false dichotomy is to point out that CO2 lagged temperature before humans started burning fossil fuels.
The 3 Pillars

The “3 Pillars model” views denial from the more strategic perspective of “how can we create denial?”

  1. Use disinformation to show people it’s “bad science”
  2. Claim the bad science is driven by radical ideology and leads to undesirable social consequences (even though conservative climate change solutions exist)
  3. Demand equal time in the media

The three pillars are related to the FLICC model like so:

  1. Logical fallacies / Cherry picking / Impossible expectations
  2. Conspiracy theories
  3. Magnified minority / Fake experts.
Denial Divergence

A study by Verheggen et al. (2014) shows that contrarians don’t agree about what, if not CO2, causes the observed warming.

More than one answer was allowed. On average, those disagreeing with the IPCC gave 2.45 reasons why, yet not one of these answers broke the 50% mark, i.e. there is no consensus among contrarians. And while “natural variability” was the most common answer, it is also pretty vague; many factors go into “natural variability”. Climatologists will tell you that “natural variability” goes up and down — not just up. Source: PBL NEAA. Question 3c (Figure 6) in the original Verheggen study also suggests that contrarians do not agree on what, if not CO2, causes global warming.

Denial may seem like a single unified movement, but individual pseudo-skeptics often have substantially different beliefs from each other.

This gives outsiders the impression that pseudo-skeptics are full of crap. Since the scientific consensus originally formed about 38 years ago, if there were any viable alternative to the mainstream theory, they’ve had more than ample time to find it and rally around it.

Those on the inside probably see the situation quite differently. My guess is that on the pseudo-skeptic hub WattsUpWithThat, these differences play out as arguments, which give pseudo-skeptics faith that they are “scientific” because they are having a “scientific debate”. This debate is not about whether humans cause a lot of warming, since they agree the answer is no — but more about which of the contrarian ideas is best.

Next time: The Denial Personality

2018 SkS Weekly Climate Change & Global Warming News Roundup #15

April 14, 2018 - 12:34pm
A chronological listing of news articles posted on the Skeptical Science Facebook Page during the past week. Editor's Pick Avoid Gulf stream disruption at all costs, scientists warn

How close the world is to a catastrophic collapse of giant ocean currents is unknown, making halting global warming more critical than ever, scientists say

  Other research this week showed that Greenland’s massive ice cap is melting at the fastest rate for at least 450 years. Photograph: Nick Cobbing/Greenpeace 

Serious disruption to the Gulf Stream ocean currents that are crucial in controlling global climate must be avoided “at all costs”, senior scientists have warned. The alert follows the revelation this week that the system is at its weakest ever recorded.

Past collapses of the giant network have seen some of the most extreme impacts in climate history, with western Europe particularly vulnerable to a descent into freezing winters. A significantly weakened system is also likely to cause more severe storms in Europe, faster sea level rise on the east coast of the US and increasing drought in the Sahel in Africa.

The new research worries scientists because of the huge impact global warming has already had on the currents and the unpredictability of a future “tipping point”. 

Avoid Gulf stream disruption at all costs, scientists warn by Damian Carrrington, Environment, Guardian, Apr 13, 2018 

Links posted on Facebook

Sun Apr 8, 2018

Mon Apr 9, 2018

Tue Apr 10, 2018

Wed Apr 11, 2018

Thu Apr 12, 2018

Fri Apr 13, 2018

Sat Apr 14, 2018

New research, April 2-8, 2018

April 13, 2018 - 5:08pm

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

Climate change impacts


1. Vulnerabilities and resilience of European power generation to 1.5 °C, 2 °C and 3 °C warming (open access)

"Results show that climate change has negative impacts on electricity production in most countries and for most technologies. Such impacts remain limited for a 1.5 °C warming, and roughly double for a 3 °C warming. Impacts are relatively limited for solar photovoltaic and wind power potential which may reduce up to 10%, while hydropower and thermoelectric generation may decrease by up to 20%. Generally, impacts are more severe in southern Europe than in northern Europe, inducing inequity between EU countries. We show that a higher share of renewables could reduce the vulnerability of power generation to climate change, although the variability of wind and solar PV production remains a significant challenge."

2. Future heat stress arising from climate change on Iran’s population health

3. Heat stress and chickens: climate risk effects on rural poultry farming in low-income countries

"Although these birds are generally known to be hardy, it appears that some losses experienced in rural poultry farming may be a direct or indirect consequence of climate-related stresses."

4. Australian climate extremes in the 21st century according to a regional climate model ensemble: Implications for health and agriculture (open access)

"Applying published heat-health relationships to projected changes in temperature shows that increases in mortality due to high temperatures for all cities examined would occur if projected future climates occurred today." ... "Assuming no adaptation or acclimatisation, published statistical relationships between drought and national wheat yield suggest that national yields will have a less than one quarter chance of exceeding the annual historical average under far future precipitation change (excluding impacts of future temperature change and CO2 fertilization)."

5. Rainfed maize yield response to management and climate covariability at large spatial scales

6. The impact of climate warming and crop management on phenology of sunflower-based cropping systems in Punjab, Pakistan

7. Identifying key meteorological factors to yield variation of potato and the optimal planting date in the agro-pastoral ecotone in North China

8. Climate change-related risks and adaptation strategies as perceived in dairy cattle farming systems in Tunisia (open access)

9. Determinants in the adoption of climate change adaptation strategies: evidence from rainfed-dependent smallholder farmers in north-central Ethiopia (Wolekasub-basin)

10. Vulnerability of communities to climate change: application of the livelihood vulnerability index to an environmentally sensitive region of China

11. Mapping urban residents’ vulnerability to heat in Abidjan, Côte d’Ivoire

12. The socio-economic vulnerability of the Australian east coast grazing sector to the impacts of climate change

13. Increasing the effectiveness of environmental decision support systems: lessons from climate change adaptation projects in Canada and Australia

14. Spatial analysis of the benefits and burdens of ecological focus areas for water-related ecosystem services vulnerable to climate change in Europe (open access)

15. Stabilization of global temperature at 1.5°C and 2.0°C: implications for coastal areas

16. American archives and climate change: risks and adaptation (open access)

"Susceptibility to climate change threats like sea level rise, storm surge, surface water flooding, and humidity, all influenced by a combination of temperature rise and increased precipitation, at a worst-case scenario were assessed for 1,232 archival repositories. Results indicate that approximately 98.8% of archives are likely to be affected by at least one climate risk factor, though on average, most archives are at low risk of exposure (90%) when risk factors are combined."

17. Minimizing irrigation water demand: An evaluation of shifting planting dates in Sri Lanka

18. Damage to buildings and structures due to recent devastating wind hazards in East Asia

19. A media framing analysis of urban flooding in Nigeria: current narratives and implications for policy (open access)

20. The effect of geographical and climatic properties on grass pollen and Phl p 5 allergen release

21. Mainstreaming climate adaptation: taking stock about “what works” from empirical research worldwide (open access)

22. Unpacking local impacts of climate change: learning with a coastal community in Central Vietnam

23. A framework for pluvial flood risk assessment in Alexandria considering the coping capacity

24. Simulating the dynamics of individual adaptation to floods

25. A global network for operational flood risk reduction (open access)

26. Climate variability, change and potential impacts on tourism: Evidence from the Zambian side of the Victoria Falls

27. Provision of Climate Services for Agriculture: Public and Private Pathways to Farm Decision-making (open access)


28. Soil microbial biomass, activity and community composition along altitudinal gradients in the High Arctic (Billefjorden, Svalbard) (open access)

29. Drivers of spatial variability in greendown within an oak-hickory forest landscape

30. Experimental strategies to assess the biological ramifications of multiple drivers of global ocean change—A review

31. Elevated CO2 and water addition enhance nitrogen turnover in grassland plants with implications for temporal stability

32. Herbivory and eutrophication mediate grassland plant nutrient responses across a global climatic gradient (open access)

33. Atmospheric and geogenic CO2 within the crown and root of spruce (Picea abies L. Karst.) growing in a mofette area

34. Experimental strategies to assess the biological ramifications of multiple drivers of global ocean change—A review

35. Climate change accelerates local disease extinction rates in a long‐term wild host–pathogen association

"We show how the incidence of disease and its severity declines over that period and most importantly demonstrate a positive association between a long‐term trend of increasing extinction rates in individual pathogen populations of the metapopulation and increasing temperature. Our results are highly suggestive that changing climatic patterns, particularly mean monthly growing season (April‐November) temperature, are markedly influencing the epidemiology of plant disease in this host–pathogen association."

36. Do pelagic grazers benefit from sea ice? Insights from the Antarctic sea ice proxy IPSO25 (open access)

37. Decalcification and survival of benthic foraminifera under the combined impacts of varying pH and salinity

38. Land use strategies to mitigate climate change in carbon dense temperate forests

39. Heat shock influences the fatty acid composition of the muscle of the Antarctic fish Trematomus bernacchii

40. Seasonal associations with novel climates for North American migratory bird populations

41. Macrorefugia for North American trees and songbirds: Climatic limiting factors and multi‐scale topographic influences

42. Seasonal associations with novel climates for North American migratory bird populations

43. Essential ocean variables for global sustained observations of biodiversity and ecosystem changes

44. Climate change and an invasive, tropical milkweed: an ecological trap for monarch butterflies

45. Plant functional diversity affects climate–vegetation interaction (open access)

46. Water availability as driver of birch mortality in Hustai National Park, Mongolia

Climate change mitigation

47. Global patterns of national climate policies: Analyzing 171 country portfolios on climate policy integration

48. Negative emissions technologies and carbon capture and storage to achieve the Paris Agreement commitments

49. The legal character and operational relevance of the Paris Agreement's temperature goal

Emission reductions

50. Climate effects of non-compliant Volkswagen diesel cars (open access)

"Furthermore, in the presence of defeat devices, the climatic advantage of ‘clean diesel’ cars over gasoline cars, in terms of global-mean temperature change, is in our view not necessarily the case."

51. Digging deeper: A holistic perspective of factors affecting soil organic carbon sequestration in agroecosystems

52. Decarbonisation perspectives for the Polish economy

53. Spatial effect of factors affecting household CO2emissions at the provincial level in China: a geographically weighted regression model

54. Why are rented dwellings less energy-efficient? Evidence from a representative sample of the U.S. housing stock

55. E-bike trials' potential to promote sustained changes in car owners mobility habits (open access)

Energy production

56. The global overlap of bioenergy and carbon sequestration potential (open access)

57. Climate-wise choices in a world of oil abundance

58. Wind farm acceptance for sale? Evidence from the Danish wind farm co-ownership scheme

59. Tracking the transition to renewable electricity in remote indigenous communities in Canada

Climate change communication

60. Illuminating the link between perceived threat and control over climate change: the role of attributions for causation and mitigation

61. Public perceptions of energy policies: Predicting support, opposition, and nonsubstantive responses

Climate change

62. What Can the Internal Variability of CMIP5 Models Tell Us About Their Climate Sensitivity?

63. Changes in climate extremes, fresh water availability and vulnerability to food insecurity projected at 1.5°C and 2°C global warming with a higher-resolution global climate model (open access)

Temperature and precipitation 

64. The Effect of Hydrometeors on MSU/AMSU Temperature Observations over the Tropical Ocean

"It is shown that correcting the TMT or TLT monthly anomalies by removing the hydrometeor contamination does not significantly influence estimates of tropical mean temperature trends but it could affect the pattern of temperature trend over the tropical oceans."

65. Climatology and trends of the Euro‐Mediterranean thermal bioclimate

66. Skilful Seasonal Predictions of Summer European Rainfall

67. Evaluation of precipitation extremes over the Asian domain: observation and modelling studies (open access)

68. Implications of a decrease in the precipitation area for the past and the future (open access)

69. Investigating the trend of average changes of annual temperatures in Iran

Extreme events

70. Quantifying statistical uncertainty in the attribution of human influence on severe weather (open access)

71. Statistics of multi‐year droughts from the method for object‐based diagnostic evaluation

72. Multi-model event attribution of the summer 2013 heat wave in Korea (open access)

73. Assessment of drought during corn growing season in Northeast China

74. Early 21st century anthropogenic changes in extremely hot days as simulated by the C20C+ detection and attribution multi-model ensemble (open access)

"We apply a stationary generalized extreme value analysis to the annual maxima of the three day average of the daily maximum surface air temperature, finding that long period return values have been increased by human activities between 1 and 3 °C over most land areas."

Forcings and feedbacks

75. Effects of convective ice evaporation on interannual variability of tropical tropopause layer water vapor (open access)

76. A warming tropical central Pacific dries the lower stratosphere

77. Aerosol Absorption: Progress Towards Global and Regional Constraints (open access)

78. Aerosol optical properties and radiative effects: Assessment of urban aerosols in central China using 10-year observations

79. The utility of the historical record for assessing the transient climate response to cumulative emissions (open access)

80. Sensitivity of polar amplification to varying insolation conditions

81. Assessing the impact of volcanic eruptions on climate extremes using CMIP5 models


82. Basal Settings Control Fast Ice Flow in the Recovery/Slessor/Bailey Region, East Antarctica

83. Early 21st century spatially detailed elevation changes of Jammu and Kashmir glaciers (Karakoram–Himalaya)

"On an average the JK East (Karakoram) glaciers showed less negative elevation changes (− 0.19 ±0.22 m yr−1) compared to the JK West (Himalaya) glaciers (− 0.50 ±0.28 m yr−1)."

84. The accuracy of snow melt-off day derived from optical and microwave radiometer data — A study for Europe (open access)

85. Impacts of snow on soil temperature observed across the circumpolar north (open access)

86. Canadian snow and sea ice: historical trends and projections (open access)

87. Canadian snow and sea ice: assessment of snow, sea ice, and related climate processes in Canada's Earth system model and climate-prediction system (open access)

88. Topographic controls on the surging behaviour of Sabche Glacier, Nepal (1967 to 2017)

Carbon cycle

89. Potential of European 14CO2 observation network to estimate the fossil fuel CO2 emissions via atmospheric inversions (open access)

90. Substrate potential of last interglacial to Holocene permafrost organic matter for future microbial greenhouse gas production (open access)

Atmospheric and oceanic circulation

91. Transient vs. Equilibrium Response of the Ocean’s Overturning Circulation to Warming

"The transient response to surface warming is characterized by a shoaling and weakening of the Atlantic meridional overturning circulation (AMOC)—consistent with results from coupled climate simulations. The initial shoaling and weakening of the AMOC occurs on decadal time-scales and is attributed to a rapid warming of northern-sourced deep water. The equilibrium response to warming, in contrast, is associated with a deepening and strengthening of the AMOC. The eventual deepening of the AMOC is argued to be associated with abyssal density changes and driven by modified surface fluxes in the Southern Ocean, following a reduction of the Antarctic sea ice cover. Full equilibration of the AMOC requires a diffusive adjustment of the abyss and takes many millenia. The equilibration time-scale is much longer than most coupled climate model simulations, highlighting the importance of considering integration time and initial conditions when interpreting the deep ocean circulation in climate models. The results also show that past climates are unlikely to be an adequate analog for changes in the overturning circulation during the coming decades or centuries."

92. Stratospheric role in interdecadal changes of El Niño impacts over Europe (open access)

Other papers

General climate science

93. A New Monthly Pressure Dataset Poleward of 60°S since 1957

94. Detecting and adjusting artificial biases of long‐term temperature records in Israel


95. A “La Niña-like” state occurring in the second year after large tropical volcanic eruptions during the past 1500 years (open access)

96. Marine invertebrate migrations trace climate change over 450 million years

Climate Science Denial Explained

April 11, 2018 - 1:07pm

Lonnie Thompson, a climate scientist, was told by his doctor that he needed a heart transplant.

He denied it. “You’re crazy! I’ve been climbing the highest mountains in the world for…” he paused, mentally counted the decades.

Lonnie loved his job. He hiked up to mountain glaciers at 20,000 feet, to retrieve ice cores with the help of a solar-powered drill. He felt fine — it’s just asthma, he told himself — and as long as he needed a heart transplant, he wouldn’t be allowed to go on any more expeditions. Logically, then, his heart must be fine.

He fought his doctor for two years, and kept going on expeditions. Then while drilling in the Alps in 2011, he couldn’t get up from his tent. He couldn’t breathe. Luckily he was able to go down from the mountain, and return to the U.S. where he was admitted to an emergency room, and put on a heart pump


Truth has been a lifelong interest of mine: at first, to find out what the truth was, and then later, to figure out what techniques are useful for distinguishing truth from falsehoods.

My interest in questions of truth started with my religion. How can we be sure whether there is a God? If there is, why is it so hard to figure out which religion is true? If he exists, is He good? Would a good God behave the way we have observed? To me, these questions seemed staggeringly important, yet strangely neglected.

“Everyone is entitled to his own opinion, but not his own facts” - a quaint quote from a bygone era

Now my interest in truth has shifted, to the flows of misinformation and disinformation in society.

Last year I encountered a group on Facebook calling itself “Friends of Science”, buying ads with a simple message:

“CO2 does nothing. Why not buy another SUV?”

This led me to speak to a series of people who believe humans don’t cause (significant) global warming, to study climate science for over two months straight, to write anti-denial articles, and finally, to take a course in Global Warming Denial.

The Consensus

During a global cooling trend in the 1970s, climatologists came to a consensus of roughly 84% that CO2 was about to warm up the world. Today that consensus may be as high as 97%, at least among experienced climate scientists.

Consensus among expert climatologists. Consensus numbers are lower among novices and non-climate scientists.

“Skeptics” can easily brush those numbers aside using myths that “there’s not really a consensus”. Here are some typical arguments against the consensus:

  • “the Doran 2009 study asked only 77 climate scientists if humans were a ‘significant contributing factor — any amount could be called significant”: well, other studies explicitly asked if humans caused “most” of the warming, or asked if humans cause at least half, or more than half of warming. Changing the question doesn’t lower the consensus very much, nor does asking more climate scientists.
  • “but there’s this petition of 31,000 scientists denying human-caused global warming…” yes, but only 0.1% of those who signed it are climate scientists. The only requirement to sign it is to be an American with a science or engineering degree. Only 0.44% of roughly 7.2 million people eligible to sign it have signed it, despite a mass-mailing campaign by the OISM, the scale of which has been kept secret.
  • “in the Cook 2013 study, almost 2/3 of papers examined gave no opinion on AGW (man-made or ‘Anthropogenic’ Global Warming), so this consensus thing is a dishonest manipulation of data.” Why would every single paper have to express an opinion about that? 37% of abstracts since 1990 endorse AGW and 1% reject it, and those numbers reflect a real consensus. Whether humans cause warming is not relevant in most climatology papers, so it need not be mentioned, and if a paper doesn’t express an opinion on AGW, it doesn’t mean the scientists who wrote it don’t have an opinion. In fact, often the same author publishes several papers, and only one of them indicates an opinion on human causation. For example, Cook’s study examined 5 papers by the contrarian Roy Spencer, and only one rejects AGW (and only implicitly, at that). The 3 papers by Lonnie Thompson (our heart-condition denier) are all classified as “No Position”, but his actual opinion is clear. Other studies that gather scientists’ opinions directly show a clear consensus, too.
  • “It’s just peer pressure”: surveys answered anonymously have similar results to surveys of public statements by climate scientists.
  • “You have to agree with AGW or your funding will get cut off”: Almost 2/3 of climate science papers don’t express any opinion about human causation, so this argument doesn’t hold water; scientists can and do get funding without publicly addressing the causation question. Plus, contrarians are typically government-funded. It seems impossible to convince some people of what’s actually going on: to keep the funding going, you must be able to publish papers in a respectable journal, and to do that you must back up all claims with quantitative evidence, and use sound reasoning.
  • “So what? global warming isn’t harmful”: Scientists disagree! In a Pew survey, 77% of “domain experts who are Earth scientists” say it is “a very serious problem” and another 17% say it is “somewhat serious”. Another study found that “41% of scientists believe global climate change will pose a very great danger to the earth in the next 50 to 100 years, compared to 13% who see relatively little danger. Another 44% rate climate change as moderately dangerous.”

People typically talk about “the study” on consensus, when in fact there have been numerous studies, all showing a consensus, generally above 90% (In “Talking to Climate Skeptics” I summarize most of the studies and give links to them). Academies of science in 80 countries endorse the consensus position. None reject it.

Telling doubters about the consensus (and dispelling anti-consensus myths) often helps them change their mind about global warming. It may also help to point out that dealing with climate change will improve the economy, that it doesn’t have to be expensive or difficult if everyone chips in a little, and that various Republicans support a carbon tax.

But I'm not here to write about doubters. This is about vocal “skeptics”.

You can explain all the above facts to a self-professed “skeptic” and it never changes their mind: they simply ignore you and/or move the goalposts. For instance, I was speaking with a guy who said he “agreed” with the consensus. I quoted consensus studies saying humans cause “most” of the observed warming, but as the discussion continued he repeatedly changed the word “most” to “some”, so he could keep saying he agreed with the consensus. After I repeatedly called him out for this, his new position was that climate scientists are all dishonest (initially he denied that this was his position, but later called them scumbags), and said that consensus studies prove climate science isn’t a real science. Why? He says “real” scientists don’t conduct surveys. Months later I caught him pretending to agree with the consensus once again.

Once you’ve proven beyond any doubt that there is a consensus, their ultimate comfort is that “science isn’t done by consensus”.

Since truth does not depend on anyone’s opinion, they figure their opinion about what is true outweighs thousands of climate scientists. For them, consensus scientists, no matter their country or background, are incompetent at best, and part of a global conspiracy at worst. For them, the only thing that makes a scientist credible is having the “right” opinions.


Denial 101x is an actual 6-week course about climate science, denial techniques and denial psychology, which you can take free online.

This 3-part series is basically “Denial101x for busy people”.

For a couple of months now I’ve had a personal goal of converting one of these guys. I wanted to know, “how much evidence does it take to convince them?” I learned to take a tactful and nonpolitical approach, with as much friendliness as I could muster — which often wasn’t that much, admittedly. After learning the science inside and out, and spending dozens of hours talking to specific people who deny AGW, the answer seems to be “It’s virtually impossible. Don’t bother.” While I talked to about a dozen of these guys, I worked harder on 6 of them. My final score: 1 out of 6. My one success story? A Canadian. And it wasn't 100% success. Just sorta-kinda.

Here’s what I’ve learned by talking to these guys:

They don’t like the word “denier” (and “denialist”)

You would think that “AGW denier” is a sensible shorthand for “person who denies human-caused (Anthropogenic) Global Warming is real, or a real problem”.

But getting offended whenever someone says “denier” is a smart strategy. Either they can force you to use the word they choose, which is “skeptic”, or they have an excuse to ignore your arguments, by claiming “denier” is a “slur” which makes you untrustworthy for saying it. (Despite this concern about labels, they still call mainstream climate scientists “alarmists”.)

The word “skeptic” is inaccurate, though, since their skepticism is selective. They were taught to be “skeptics” using a series of anti-science myths. They not only believe the myths, but when I try to debunk them, they often act as though I hadn’t said anything at all. Instead they change the subject or respond only to something else that I said. Real skeptics are evidence-driven, and do not simply ignore information that refutes their position.

“Science is not a democracy. It’s a dictatorship, and it’s the evidence that does the dictating” - John Reisman

Some have suggested other terms, such as “pseudo-skeptic” and “citizen scientist”. Originally this article used the term “denier”, but I’ve decided to switch the text to use “pseudo-skeptic” in an effort to increase neutrality. I’ve reserved the word “contrarian” for those rare individuals who have credentials in climate science, but still disagree with the consensus. (Edit: George Marshall suggests “dissenters”; others have suggested “dismissive”.)

It's a political debate dressed up as a science debate

Most Americans live in the Eastern U.S., which warmed less than the global average. This may help denial, but political beliefs matter far more.

Left side in red: votes for Trump. Right side in brown: states where people do not believe “most scientists think global warming is happening”.

A Pew poll asks if “Earth is warming due mostly to human activity?” Only 15% of Republican voters agree (22% in another poll), compared to 79% of Democrat voters. It’s a testament to the power of propaganda on this issue that even Democrats show a lower consensus than climate science experts.

Graph by John Cook

The Denial Community

There are two climate scientists who publish contrarian blogs: Roy Spencer and Judith Curry, both American conservatives. The pseudo-skeptic community rallies around them as beacons of truth. Both of them want to minimize the appearance of human influence, but neither claim that there is no human influence.

Spencer wrote a book on free-market economics, and once said “I view my job a little like a legislator, supported by the taxpayer, to protect the interests of the taxpayer and to minimize the role of government”. Spencer emphasizes his own UAH dataset, which shows the smallest warming trend out of all available datasets (four different compilations of land and sea data by three countries, as well as weather balloons and RSS data, show more warming). Curry pushes an “uncertainty” angle — that we don’t know enough about what’s going on and climate scientists can’t be trusted to tell us. Pseudo-skeptics may combine such contrarian opinions with myths they’ve seen elsewhere to build a more complete story for themselves.

The tiny minority of credentialed contrarians are propped up by an enormous web of denial blogs written by non-climate scientists and non-scientists, such as “ClimateDepot” (by the Washington DC conservative outfit CFACT), the conservative Heartland Institute, WattsUpWithThat (headed by conservative TV meteorologist Anthony Watts), “RealClimateScience” (not to be confused with, a blog by real climate scientists), NoTricksZone (with writers such as Kenneth Richard who I have examined before), Tony Heller (a longtime conspiracy theorist who used to go by the alias Steve Goddard), JoNova, and “Friends of Science”. Even publications like Washington Post and Forbes have published articles from professional pseudo-skeptics like James Taylor (Heartland Institute), and the New York Times recently hired conservative pseudo-skeptic Bret Stephens.

Next time: Tactics of Denial

¹ Story adapted from a Denial101x interview

New resource: The Fact-Myth-Fallacy slide-deck

April 9, 2018 - 1:15am

Many of you will already be familiar with the Fact-Myth-Fallacy structure of a successful debunking. For a refresher, John Cook's post about "Inoculation theory: Using misinformation to fight misinformation" is a good primer on the topic.

As examples for how to make use of this structure, we have short debunkings of many of the myths covered in our MOOC Denial101x readily available on an overview page, which also includes the relevant video lecture for each of them. The list is also available as a PDF-file:

Based on this FMF-page, I created a slide-deck with one page for each debunking and an index-page utilising the short URL "code" for each rebuttal to quickly access them. Instead of a video, each slide includes a graphic to drive home the main point of the debunking. Several of the graphics were created by John Garrett (jg) specifically for this slide-deck. They have been added to our graphics resources.

This slide-deck can serve several purposes. It can be used stand-alone to briefly explain some aspects of climate science. It can be tacked on to presentations used in public talks where a Q&A or discussion section is included at the end. There's always a chance that somebody who disagrees with or outright denies the science is in the audience just waiting to raise her or his hand after your talk! Armed with slides like the ones presented here, you'll be prepared to tackle (most of) them - and while doing so, show the rest of the audience that the objection has already been tackeled and debunked.

Obviously, this slide-deck is just a start. More debunkings can be added, graphics can be replaced or tweaked as needed, and the format can be adapted to other topics.

You can download the slide-deck either as a PDF (2.4MB) or PPTX (14MB). The navigation from the index page to each debunking and back works in both versions but the PPTX also includes some animations where the content of each slide is revealed in stages.

Here is hoping that this will become a helpful resource! Please let us know in the comments if and where you made use of it and how it went. Also feel free to post suggestions for other/better graphics to use on individual slides.

2018 SkS Weekly Climate Change & Global Warming Digest #14

April 8, 2018 - 12:56pm

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

Story of the Week... Solar geoengineering ‘too uncertain to go ahead yet’

The world must urgently agree controls on solar geoengineering to weigh up its possible risks and benefits before deciding to go ahead, one expert says.

Brightening marine clouds is one suggested solar geoengineering approach. Image: By Ron Reeves, US Navy, via Wikimedia Commons

Progress to deploy solar engineering, experimental technology designed to protect the world against the impact of the changing climate, must pause, a former United Nations climate expert says, arguing that governments need to create “effective guardrails” against any unforeseen risks.

Janos Pasztor, who served as a UN assistant secretary-general on climate change, is using a speech to Arizona State University, broadast via Facebook Live by ASU LightWorks, 6:30-8pm Arizona time (9:30pm EDT – US Eastern Daylight Time) today, to warn the world that governments are largely ignoring the fundamental question of who should control geoengineering, and how.

There are widespread misgivings, both among scientists and more widely, about geoengineering, with many regarding it as at best a strategy of last resort to help to avoid calamitous climate change.

Mr Pasztor’s warning comes as researchers prepare for what is thought to be the world’s first outdoor experiment on stratospheric aerosol injection (SAI), one type of solar geoengineering. The test is due to take place later this year over Arizona.

Pasztor heads the Carnegie Climate Geoengineering Governance Initiative(C2G2),  an initiative of the New York-based Carnegie Council for Ethics in International Affairs. The Initiative wants solar geoengineering deployment to be delayed until the risks and potential benefits are better known and governance frameworks are agreed.

Solar geoengineering ‘too uncertain to go ahead yet’ by Alex Kirby, Climate News Network, Apr 6, 2018 

Opinion of the Week...

A new Gallup survey shows that independent voters are less concerned about climate change than they were a year ago. In the last year, independents have become less likely to accept that global warming is happening and that humans are the cause, and less likely to perceive that there’s a scientific consensus about global warming.

In 2017, 71 percent of independent voters were aware that most scientists believe global warming is occurring; this year it’s 65 percent. There has long been a significant gap between public perception of global warming and the scientific consensus: Between 90 percent and 100 percent of climate scientists agree humans are causing global warming, with studies converging on 97-percent consensus. But surveys since 2010 offered hope that the “consensus gap” had been shrinking over the last eight years. Gallup’s new data indicates this trend has reversed. The consensus gap widened over the last year.

Independents aren’t the only ones on the move. The American public has become more polarized on climate change in the last year: Climate concern and acceptance has dropped among Republicans, and Democrats have become more accepting of climate change.

There are a few ways to account for these shifts in public opinion. One is the cues we’ve heard from our political leaders, which are a leading driver of people’s concerns and perceptions about climate change.

Trump’s Climate Change Denial Is Already Reshaping Public Opinion. Opinion by John Cook, HuffPost, Apr 3, 2018 

SkS Highlights... Carnegie Climate Geoengineering Governance Initiative

C2G2 seeks to catalyze the creation of effective governance for climate geoengineering technologies by shifting the conversation from the scientific and research community to the global policy-making arena, and by encouraging a broader, society-wide discussion about the risks, potential benefits, ethical and governance challenges raised by climate geoengineering.

The C2G2 initiative is not for or against the research, testing or potential use of climate geoengineering technologies. That is a choice for society to make.

 C2G2 is an initiative of the Carniege Council for Ethics in International Affairs

Toon of the Week...


Quote of the Week...

Critics say the National Park Service’s editing of the report reflects unprecedented political interference in government science at the Interior Department, which oversees the park service.

Jonathan Overpeck, a climate scientist and dean of the University of Michigan’s School for Environment and Sustainability, said the deletions are “shocking from a scientific point of view, but also from a policy point of view.”

“To remove a very critical part of the scientific understanding is nothing short of political censorship and has no place in science,” he said. “Censorship of this kind is something you’d see in Russia or some totalitarian regime. It has no place in America.”

Wipeout: Human role in climate change removed from science report by Elizabeth Shogren, Reveal, Apr 2, 2018 

SkS Spotlights...

The Climate Atlas of Canada is an interactive tool for citizens, researchers, businesses, and community and political leaders to learn about climate change in Canada. It combines climate science, mapping and storytelling to bring the global issue of climate change closer to home, and is designed to inspire local, regional, and national action and solutions.

The Atlas explains what climate change is, how it affects Canada and what these changes mean in our communities.  Various aspects of climate change can be explored using maps, graphs and climate data for provinces, local regions and cities across the country. Plain-language description and analysis make climate science understandable and meaningful.  

Documentary videos, collaboratively developed with local and Indigenous knowledge holders as well as other experts, help make local sense of the global issue of climate change. These voices of lived experience provide personal perspectives that complement the climate data and help explain the reality and the meaning of climate change in Canada.

The Atlas is one of the only tools in the world that integrates interactive web design with climatology, cinema, and cartography to connect scientific data with personal experience in compelling and easy-to-use ways.

Coming Soon on SkS...
  • New resource: The Fact-Myth-Fallacy slide-deck (Baerbel, JG)
  • EPA’s war with California over fuel efficiency proves America needs a carbon tax (Dana)
  • Climate denial explained Part 1 (qwertle)
  • Scientists are marching Saturday to make politicians listen to evidence (Dana)
  • New research this week (Ari)
  • 2017 SkS Weekly Climate Change & Global Warming News Roundup #15 (John Hartz)
  • 2017 SkS Weekly Climate Change & Global Waming Digest #15 (John Hartz)
Poster of the Week...


Climate Feedback Reviews... Rush Limbaugh falsely claims there is no evidence of human-caused global warming


"There isn’t yet any empirical evidence for their claim that greenhouse gases even cause temperatures to increase."



Rush LimbaughThe Rush Limbaugh Show, April 2, 2018


Factually Inaccurate: It is an unequivocal fact that Earth’s climate has warmed over the past century. Also, the conclusion that the human-caused increase of greenhouse gases is causing warming is supported by a wide range of empirical data.

Key Take Away 

Human-caused global warming is not a theoretical, future prediction—it has already occurred. Warming of the atmosphere and oceans is extensively documented, and the role of increased greenhouse gases in this warming has been determined from multiple lines of evidence.

Rush Limbaugh falsely claims there is no evidence of human-caused global warming by Scott Johnson, Climate Feedback, Apr 4, 2018

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



Michael Oppenheimer's bio page

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2018 SkS Weekly Climate Change & Global Warming News Roundup #14

April 7, 2018 - 1:14pm
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week.  Editor's Pick March is 3rd warmest on record, many contrasts


March 2018 was the third warmest on record, according to the European Centre for Medium Range Weather Forecasting Copernicus Climate Change service.

Although not as exceptional as the values for March 2016 and March 2017, it was in line with the upward trend of 0.18°C per decade seen in global temperature data from 1979 onwards, according to the monthly report.

March 2018 was colder than the 1981-2010 average over almost all of Europe. Only in the far north and over the far southeast of the continent was it warmer than average. Below average temperatures occurred over almost all of northern Russia and over the northern USA and southern Canada.

Within Europe, Spain had 163 mm of rainfall – more than three times the long-term average of 47 mm (1981-2000), making it one of the wettest months of March on record, according to the national meteorological service AEMET.

In France, Mediterranean regions saw two to four times more rain than average. For instance Province-Alpes, the Cote d’Azure and Corsica had the second wettest March after 2013, according to Météo-France. 

March is 3rd warmest on record, many contrasts, Media Release, World Meterologial Association (WMO), Apr 6, 2018

Links posted on Facebook

Sun Apr 1, 2018

Mon Apr 2, 2018

Tue Apr 3, 2018

Wed Apr 4, 2018

Thu Apr 5, 2018

Fri Apr 6, 2018

Sat Apr 7, 2018

New research, March 26 - April 1, 2018

April 6, 2018 - 4:21pm

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

Climate change

1. Consistency of climate change projections from multiple global and regional model intercomparison projects

2. Uncertainty in projected climate change arising from uncertain fossil-fuel emission factors (open access)

3. Skillful climate forecasts of the tropical Indo-Pacific Ocean using model-analogs

Temperature, precipitation, and wind

4. A new integrated and homogenized global monthly land surface air temperature dataset for the period since 1900

"A new dataset of integrated and homogenized monthly surface air temperature over global land for the period since 1900 [China Meteorological Administration global Land Surface Air Temperature (CMA-LSAT)] is developed. In total, 14 sources have been collected and integrated into the newly developed dataset, including three global (CRUTEM4, GHCN, and BEST), three regional and eight national sources. Duplicate stations are identified, and those with the higher priority are chosen or spliced. Then, a consistency test and a climate outlier test are conducted to ensure that each station series is quality controlled. Next, two steps are adopted to assure the homogeneity of the station series: (1) homogenized station series in existing national datasets (by National Meteorological Services) are directly integrated into the dataset without any changes (50% of all stations), and (2) the inhomogeneities are detected and adjusted for in the remaining data series using a penalized maximal t test (50% of all stations). Based on the dataset, we re-assess the temperature changes in global and regional areas compared with GHCN-V3 and CRUTEM4, as well as the temperature changes during the three periods of 1900–2014, 1979–2014 and 1998–2014. The best estimates of warming trends and there 95% confidence ranges for 1900–2014 are approximately 0.102 ± 0.006 °C/decade for the whole year, and 0.104 ± 0.009, 0.112 ± 0.007, 0.090 ± 0.006, and 0.092 ± 0.007 °C/decade for the DJF (December, January, February), MAM, JJA, and SON seasons, respectively. MAM saw the most significant warming trend in both 1900–2014 and 1979–2014. For an even shorter and more recent period (1998–2014), MAM, JJA and SON show similar warming trends, while DJF shows opposite trends. The results show that the ability of CMA-LAST for describing the global temperature changes is similar with other existing products, while there are some differences when describing regional temperature changes."

5. Extreme temperature events on Greenland in observations and the MAR regional climate model (open access)

6. Altitude-temporal behaviour of atmospheric ozone, temperature and wind velocity observed at Svalbard

7. Recent intensified impact of December Arctic Oscillation on subsequent January temperature in Eurasia and North Africa

8. A 305-year continuous monthly rainfall series for the island of Ireland (1711–2016) (open access)

9. Origins of the decadal predictability of East Asian land summer monsoon rainfall

10. Observed diurnal temperature range variations and its association with observed cloud cover in northern Pakistan

11. Precipitation Intensity Changes in the Tropics from Observations and Models

12. Southern Ocean heat uptake, redistribution and storage in a warming climate: The role of meridional overturning circulation

13. An urban-based climatology of winter precipitation in the northeast United States

14. Evaluating SST analyses with independent ocean profile observations

Extreme events

15. 1984 Ivanovo tornado outbreak: Determination of actual tornado tracks with satellite data

16. Tropical cyclogenesis in warm climates simulated by a cloud-system resolving model

17. Simulating seasonal tropical cyclone intensities at landfall along the South China coast

18. Relationship between South China Sea summer monsoon onset and landfalling tropical cyclone frequency in China

19. On the nonlinearity of spatial scales in extreme weather attribution statements

20. Climate warming enhances snow avalanche risk in the Western Himalayas (open access)

21. Land-cover Change and the “Dust Bowl” Drought in the U.S. Great Plains

"This study uses high-resolution modeling experiments and quantifies an effect of the particular Great Plains land-cover in the 1930s that weakens the southerly moisture flux to the region. This effect lowers the average precipitation, making the Great Plains more susceptible to drought. When drought occurs, the land-cover effect enhances its intensity and prolongs its duration. Results also show that this land-cover effect is comparable in magnitude to the effect of the 1930s large-scale circulation anomaly. Finally, analysis of the relationship of these two effects suggests that while lowering the precipitation must have contributed to the Dust Bowl drought via the 1930s land-cover effect, the initiation of and recovery from that drought would likely result from large-scale circulation changes, either of chaotic origin or resulting from combinations of weak SST anomalies and other forcing."

22. Assessing variations of extreme indices inducing weather-hazards on critical infrastructures over Europe—the INTACT framework

23. Time‐sensitive analysis of a warming climate on heat waves in Saudi Arabia: Temporal patterns and trends

24. Increasing concurrent drought and heat during the summer maize season in Huang–Huai–Hai Plain, China

25. Projected changes in climate extremes in China in a 1.5 °C warmer world

26. Drought characteristics over China during 1980–2015

27. Modelling serial clustering and inter‐annual variability of European winter windstorms based on large‐scale drivers (open access)

Forcings and feedbacks

28. The impact of aerosol emissions on the 1.5 °C pathways (open access)

29. The Present and Future of Secondary Organic Aerosol Direct Forcing on Climate

30. Characterization of aerosol optical properties and model computed radiative forcing over a semi-arid region, Kadapa in India

31. Heavy aerosol pollution episodes in winter Beijing enhanced by radiative cooling effects of aerosols (open access)

"From clean stages to transport stages (TS) to cumulative stages (CS) in HPEs, surface direct and global radiation sharply diminish, with daily the cumulative sum of radiant exposure reduced by 89% and 56% respectively from clean stages to CSs."

32. Quantify contribution of aerosol errors to cloud fraction biases in CMIP5 Atmospheric Model Intercomparison Project simulations

33. Quantifying the contribution of different cloud types to the radiation budget in southern West Africa

34. Hindcast skill improvement in Climate Forecast System (CFSv2) using modified cloud scheme

35. Relationship between lightning and solar activity for recorded between CE 1392–1877 in Korea

36. Determining the infrared radiative effects of Saharan dust: a radiative transfer modelling study based on vertically resolved measurements at Lampedusa (open access)

37. The role of sea-ice albedo in the climate of slowly rotating aquaplanets (open access)


38. Assessing ice margin fluctuations on differing timescales: Chronological constraints from Sermeq Kujatdleq and Nordenskiöld Gletscher, central West Greenland

39. Seasonal and regional manifestation of Arctic sea ice loss

"The Arctic Ocean is currently on a fast track towards seasonally ice-free conditions. Although most attention has been on the accelerating summer sea ice decline, large changes are also occurring in winter. This study assesses past, present, and possible future change in regional Northern Hemisphere sea ice extent throughout the year by examining sea ice concentration based on observations back to 1950, including the satellite record since 1979. At present, summer sea ice variability and change dominate in the perennial ice covered Beaufort, Chukchi, East Siberian, Laptev, and Kara seas, with the East Siberian Sea explaining the largest fraction of September ice loss (22%). Winter variability and change occur in the seasonally ice covered seas further south; the Barents Sea, Sea of Okhotsk, Greenland Sea, and Baffin Bay, with the Barents Sea carrying the largest fraction of loss in March (27%). The distinct regions of summer and winter sea ice variability and loss have generally been consistent since 1950, but appear at present to be in transformation due to the rapid ice loss in all seasons. As regions become seasonally ice-free, future ice loss will be dominated by winter. The Kara Sea appears as the first currently perennial ice covered sea to become ice-free in September. Remaining on currently observed trends, the Arctic shelf seas are estimated to become seasonally ice-free in the 2020s, and the seasonally ice-covered seas further south to become ice-free year-round from the 2050s."

40. Atmospheric influences on the anomalous 2016 Antarctic sea ice decay (open access)

41. Quantifying vulnerability of Antarctic ice shelves to hydrofracture using microwave scattering properties

42. Spatio‐temporal November and March snowfall trends in the Lake Michigan region


43. Hydrological impacts in La Plata basin under 1.5, 2 and 3 °C global warming above the pre‐industrial level

44. Twentieth-Century Climate Change over Africa: Seasonal Hydroclimate Trends and Sahara Desert Expansion

"It is shown that the Sahara Desert has expanded significantly over the twentieth century, by 11%–18% depending on the season, and by 10% when defined using annual rainfall."

45. Decadal Shift of NAO-Linked Interannual Sea Level Variability along the US Northeast Coast

Carbon cycle

46. Carbon dioxide emissions from the flat bottom and shallow Nam Theun 2 Reservoir: drawdown area as a neglected pathway to the atmosphere

47. Effects of contemporary land-use and land-cover change on the carbon balance of terrestrial ecosystems in the United States (open access)

48. Upland grasslands in Northern England were atmospheric carbon sinks regardless of management regimes

Atmospheric and oceanic circulation

49. How well do we know ENSO’s climate impacts over North America, and how do we evaluate models accordingly?

50. Collapse of the 2017 Winter Beaufort High: A Response to Thinning Sea Ice?

"The collapse of the Beaufort High during the winter of 2017 was associated with simultaneous 2‐sigma sea level pressure, surface wind, and sea ice circulation anomalies in the western Arctic. As the Arctic sea ice continues to thin, such reversals may become more common and impact ocean circulation, sea ice, and biology."

51. Interdecadal variability of the Warm Arctic and Cold Eurasia pattern and its North Atlantic origin

Climate change impacts


52. Climate change and pastoralists: perceptions and adaptation in montane Kenya

"All participants reported changes in the amount and distribution of rainfall, fog, temperature and wind for the past 20–30 years; regardless of the mountain or ethnicity. They particularly highlighted the reduction in fog. Meteorological evidence on rainfall, temperature and fog agreed with local perceptions; particularly important was a 60% reduction in hours of fog per year since 1981. Starting farming and shifting to camel herding were the adaptive strategies most commonly mentioned."

53. Climate change adaptation measure on agricultural communities of Dhye in Upper Mustang, Nepal

54. Understanding climate change impacts on water buffalo production through farmers’ perceptions (open access)

55. Climate information? Embedding climate futures within temporalities of California water management

56. The effect of hot days on occupational heat stress in the manufacturing industry: implications for workers’ well-being and productivity (open access)

57. Exertional heat illness incidence and on-site medical team preparedness in warm weather


58. Detecting early warning signals of tree mortality in boreal North America using multiscale satellite data

"Overall, results indicate potential to use satellite NDVI for early warning signals of mortality. Relationships are broadly consistent across inventories, species, and spatial resolutions, although the utility of coarse‐scale imagery in the heterogeneous aspen parkland was limited. Longer‐term NDVI data and annually remeasured sites with high mortality levels generate the strongest signals, although we still found robust relationships at sites remeasured at a typical 5 year frequency."

59. Evaluation of land surface phenology from VIIRS data using time series of PhenoCam imagery

60. Uniform shrub growth response to June temperature across the North Slope of Alaska (open access)

61. Response of terrestrial evapotranspiration to Earth's greening

62. Ecological shift and resilience in China's lake systems during the last two centuries

63. Background sampling and transferability of species distribution model ensembles under climate change

64. Cidaroids spines facing ocean acidification

65. Ecosystem-based monitoring in the age of rapid climate change and new technologies

66. Moderate hypoxia but not warming conditions at larval stage induces adverse carry-over effects on hypoxia tolerance of European sea bass (Dicentrarchus labrax) juveniles

Other impacts

67. Future southcentral US wildfire probability due to climate change

Climate change mitigation

68. Pathways to deliberative capacity: the role of the IPCC

69. Optimal carbon taxes for China and implications for power generation, welfare, and the environment

70. Between Scylla and Charybdis: Delayed mitigation narrows the passage between large-scale CDR and high costs (open access)

Energy production

71. The role of large—scale BECCS in the pursuit of the 1.5°C target: an Earth system model perspective (open access)

72. Evaluating the use of biomass energy with carbon capture and storage in low emission scenarios (open access)

Climate change communication

73. Comparing smallholder farmers’ perception of climate change with meteorological data: Experience from seven agro-ecological zones of Tanzania

74. Learn to conserve: The effects of in-school energy education on at-home electricity consumption

Other papers

75. Climate change and society in the 15th to 18th centuries

"Overall, research that connects climatic and social histories has suggested that human decisions, political structures, economic arrangements, institutions, and cultures either magnified or mitigated the impact of climate change on the societies of the early modern world."

76. Prevalence of environmental annoyance in a Swedish and Finnish general population: Impact of everyday exposures on affect and behavior

77. Air quality and human health impacts of grasslands and shrublands in the United States


78. A late-Holocene pollen record from the western Qilian Mountains and its implications for climate change and human activity along the Silk Road, Northwestern China

79. Reconstruction of high‐resolution climate data over China from rainfall and snowfall records in the Qing Dynasty

80. Climatic signals in stable carbon isotope ratios of Juniper and Oak tree rings from northern Iran

American conservatives are still clueless about the 97% expert climate consensus

April 5, 2018 - 1:45am

Gallup released its annual survey on American perceptions about global warming last week, and the results were a bit discouraging. While 85–90% of Democrats are worried about global warming, realize humans are causing it, and are aware that most scientists agree on this, independents and Republicans are a different story. Only 35% of Republicans and 62% of independents realize humans are causing global warming (down from 40% and 70% last year, respectively), a similar number are worried about it, and only 42% of Republicans and 65% of independents are aware of the scientific consensus – also significantly down from last year’s Gallup poll.

The Trump administration’s polarizing stance on climate change is probably the main contributor to this decline in conservative acceptance of climate change realities. A recent study found evidence that “Americans may have formed their attitudes [on climate change] by using party elite cues” delivered via the media. In particular, the study found that Fox News “is consistently more partisan than other [news] outlets” and has incorporated politicians into the majority of its climate segments.

Americans are gradually becoming better-informed

Nevertheless, public awareness about climate change realities has improved over the long-term. For example, about two-thirds of Americans now realize that most scientists agree global warming is occurring, up from less than half in 1997.

Responses to Gallup survey question asking whether most scientists believe global warming is occurring. Illustration: Dana Nuccitelli

There’s also a strong correlation between awareness of the expert consensus, that humans are causing global warming, and concern about the issue. This suggests that when people are aware that experts agree, they accept the consensus and realize we need to address the problem. This is consistent with research finding that the expert consensus is a ‘gateway belief’ leading to public support for climate action.

Responses to Gallup survey questions asking whether scientists agree global warming is occurring (blue), whether humans are responsible (orange), and whether respondents are worried about it (black). Illustration: Dana Nuccitelli

There’s a handbook for that

John Cook and Stephan Lewandowsky, who previously published The Debunking Handbook, teamed up with Sander van der Linden and Edward Maibach to write The Consensus Handbook. It’s a concise and definitive summary of everything related to the expert climate consensus, including how we know 90–100% of climate scientists agree on human-caused global warming, efforts to manufacture doubt about the consensus, its role as a gateway belief, its neutralizing effect on political ideology, and how to inoculate people against misinformation.

Those last points are particularly important in light of the Gallup survey data. There’s an intense battle over public opinion on climate change, with cues from political elites having a polarizing effect that’s largely offset when people become aware of the expert consensus. 

Thus, there’s been a concerted campaign to misinform people about the consensus. That was a key issue that major oil companies accepted in a recent court case, while their fossil fuel-funded supporters denied the consensus in briefs submitted to the court. Meanwhile, the Trump EPA is distributing misleading statements about scientific uncertainty on climate change, helping create this tribal identity that ‘Team Conservative’ denies the realities and dangers associated with human-caused global warming.

However, as the Consensus Handbook discusses, research has shown that inoculating people against misinformation can largely offset its influence.

The effect of different types of messages about climate change. Illustration: The Consensus Handbook.

The bad news is that misinformation can totally offset the influence of facts on topics like the expert consensus on human-caused global warming. The good news is that people don’t like being fooled, so when they’re additionally informed about the tactics used to trick them with misinformation, they’re more likely to accept the facts.

Some are polarized, but many are simply unaware

The challenge is that politicians on Fox News and other media outlets are able to reach a wide audience with their polarizing messages about climate change. Reaching a similarly sized audience not only with facts but also inoculation against the misinformation is a daunting task. However, as John Cook notes,

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Skeptical Science at EGU 2018

April 4, 2018 - 10:06am

Next week, about 14,000 scientists will meet in Vienna, Austria for the European Geosciences Union General Assembly 2018. Skeptical Science will make an appearance in a few of the thousands of sessions held from April 9 to 13.

Here are the sessions with SkS involvement:

Stephan Lewandowsky, Kevin Cowtan and Ari Jokimäki are co-authors for an oral presentation given by Stefan Rahmstorf on Monday:

Detecting and attributing climate change: trends, extreme events, and impacts
Convener: Pardeep Pall
Co-Conveners: Alexis Hannart , Seung-Ki Min , Aurélien Ribes

Bärbel Winkler will be one of the panelists in a short course about fighting misinformation convened by Bárbara Ferreira offered on Monday afternoon:

Session SC2.12 ECS
Debunking myths and fake news: how can geoscientists fight misinformation and false claims
Convener: Bárbara Ferreira  | Co-Convener: Olivia Trani    
Mon, 09 Apr, 15:30–17:00 / Room -2.91

On Wednesday we'll have John Cook's Denial101x poster presented by Bärbel Winkler in a session about climate change education:

Session EOS13
Climate Change Education
Convener: Robin Matthews  | Co-Conveners: Anne Gold , Helena Martins , David Wilgenbus , Sylvia Knight
Orals - Wed, 11 Apr, 10:30–12:00 / Room L7
Posters - Attendance Wed, 11 Apr, 15:30–17:00 / Hall X1

We plan to blog about these and other sessions during and after EGU2018.

Scientists examine threats to food security if we meet the Paris climate targets

April 3, 2018 - 1:50am

We have delayed action for so long on handling climate change, we now can no longer can “will it happen?” Rather we have to ask “how bad will it be?” and “what can be done about it?” As our society thinks about what we should do to reduce our carbon pollution and the consequences of electing science-denying politicians, scientists are actively studying the pros and cons of various emission reductions. 

Readers of this column have certainly heard about temperature targets such as 1.5°C or 2°C. These targets refer to allowable temperature increases over pre-industrial temperatures. If humans take action to hit a 1.5°C target, it means we are committed to keeping the human-caused global temperature rise to 1.5°C. Similarly for a 2°C target.

The lower the target, the smaller the climate change. The smaller the climate change, the better. But is it worth the effort to set lower targets? I mean, if 2°C is good enough, why take the trouble to keep temperatures within 1.5°C?

Fortunately, a new paper just out in the Philosophical Transactions of the Royal Society A asks this question. Specifically, they ask “How much larger are the impacts at 2°C compared to 1.5°C?” A follow-on question asked by the authors relates to what conditions occur at a particular level of warming, such as 2°C. This is a really important question because policymakers need to know what it will take to adapt to a 1.5°C world or a 2°C world.

The authors focus on the impact of climate change on food security, and in particular, how changes to extreme weather will impact food production. The weather issues that are central to this study are drought and precipitation. We know that in a warming world, the weather will get wetter. This is because warm air is more able to hold water (air can be more humid). As a consequence, when rains fall, they come in heavier bursts. We are already seeing this in the US, for example, where the most extreme rainfalls are increasing across the country.

But, at the same time, evaporation happens quicker and areas can dry out faster. So, when the rains stop, drought can set in quicker and more severely.

So, there are competing issues and an obvious question is, which will win out? Will the world become drier or wetter? The answer to this question depends on where you live. It is likely that areas that are currently wet will become wetter. Areas that are currently dry will become drier. This is just a general rule of thumb, there are variations to this rule. But it is a pretty good generalization.

This behavior is vexing for farmers because it makes planning for the future complicated. But this study at least shines some light on the subject and helps us prepare. To complete the study, the authors considered an Earth that has 1.5°C warming and another Earth with 2°C warming. The authors then identified specific measures for extreme weather. Among the measures are the annual maximum temperature, the percentage of days with extreme daily temperatures, the number of consecutive dry days, and the maximum rainfall in a 5-day period. 

Measures of heavy rainfall and drought were combined with societal factors to form a Hunger and Climate Vulnerability Index. The index incorporates how exposed a country is to climate hazards, how sensitive a country’s agriculture is to climate hazards, and how able a country is to adapt. With these metrics and indices calculated for 122 countries in the developing and under-developed parts of the globe, the authors show that some areas will be more impacted than others.

Increased wetness will affect Asia more than other regions. Among their predictions is that the water flowrate in the Ganges river may increase by 100%. However, increases to drought could hit Africa and South America hardest. An example outcome is that the Amazon river flow may decrease by 25%. They also found that for most of the planet, a 2°C world is worse than a 1.5°C world. This is to be expected, but now there is a way to quantify the impact of incremental increases in temperature on societal impact.

When the authors continued their look at various regions, that found that temperature changes are amplified in some locations. For instance, with a 2°C warmer world, the land areas mostly warm by more than 2°C. In some regions, like North America, China, northern Asia, northern South America, and Europe, the daily high temperature increases could be double that of the globe on average.

In the figure below, the Hunger and Climate Variability Index is shown for a 2°C warmer world. The image is scaled according to how vulnerable they are to food insecurity. Countries with a larger value are more vulnerable than countries with a smaller number. Any country with a vulnerability greater than 1 is more vulnerable than any country today.

Hunger and Climate Vulnerability Index for 2°C global warming. Illustration: Betts et al. (2018), Philosophical Transactions of the Royal Society A

As lead author Richard Betts explained,

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On climate change, zero-sum thinking doesn't work

April 2, 2018 - 1:31am

Joseph Robertson is Global Strategy Director for Citizens’ Climate Lobby, Founder and President of the Geoversiv Foundation, and lead strategist in the Resilience Intel initiative.

Democracy is not a zero-sum game. Behaving as if it is degrades democratic process and our personal political sovereignty.

A zero-sum game is a contest for control of finite resources. Whatever one gains, another must lose. When two or more candidates compete for a single public office, only one can win, so many people view politics as bloodsport, applying “winner takes all” thinking to everything political. But elected officials are not conquerors; they are sworn servants to all their constituents.

The beating heart of a free society is the guarantee of personal political sovereignty, safeguarded by transparent institutions, checks and balances, and a free press.

Political sovereignty is informational sovereignty. Disinformation disempowers. Distortion of our informational environment has slowed humanity’s overall effort to eliminate corruption and transcend harmful practices, like those that destabilize Earth’s climate.

Snapshot of the ‘Peace Synapse’ relational synaptic graph of climate, peace and security knowledge relationships, spanning the period 2009-2016. Photograph: Geoversiv Foundation, using the GDELT global knowledge graphing system.

What corrosive hyper-partisanship misses is that human intelligence, creative collaboration, and adherence to basic principles of fairness, make more good possible and so result in real value added — throughout the system, for the benefit of everyone.

Success requires dealing ably with complexity.

Neurons in the human brain organize themselves into vast 7-dimensional sandcastle structures — flashes of consciousness that emerge and disappear in millionths of a second. Brains are organic synaptic networks. More connections mean more possibilities – more “going on.” Bigger, more complex constellations of neural-attentive cohesion are effectively a bigger landscape for thoughtful attention, recall and imagination — an expanded, diversified space for figuring out what needs figuring.

Zero-sum thinking strips intelligence from our politics. Generative thinking recognizes that complex constructive interactions make us smarter, more capable, freer, and more secure.

The unauthorized use of 50 million Facebook users’ data to corrupt the informational environment touching 57 billion “friend pairs” to induce a desired voting response appears to have been a deliberate effort to degrade the personal informational sovereignty of American voters. Illustration: Joseph Robertson

At the human scale, we naturally demand trustworthy generative value-building be an organic part of our experience. If we are informationally sovereign, we can scale up smart decision-making to correct hidden market failures and expand routine access to increased value for everyone.

To distort and disrupt climate and energy decision-making, carbon pollutersspent hundreds of millions of dollars over several decades. Their aim was to degrade the sovereignty of voters, consumers, rivals in the innovation space, the free press, and even nation states.

Such corrosive behaviors have undermined the competitiveness of polluting industries, making outdated methods appear longer lived than they stand a real chance of being, even as they build up unprecedented, nonlinear carbon liability. Market forces will eventually stop rewarding ever more costly carbon-intensive practices that put irreplaceable natural life-supports at risk.

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2018 SkS Weekly Climate Change & Global Warming News Roundup #13

March 31, 2018 - 1:10pm
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week.  Editor's Pick Stanford law and science experts discuss court case that could set precedent for climate change litigation

A closely watched federal trial pitting two cities against major oil companies has taken surprising and unorthodox turns. Stanford researchers examine the case, which could reshape the landscape of legal claims for climate change-related damages.

A federal trial pitting two cities against major oil companies could reshape the landscape of legal claims for climate change-related damages. (Image credit: Walter Siegmund/Wikimedia Commons)

A judge in California took an unusual step in trying to untangle who is to blame for increasingly frequent droughts, floods and other climate change-related extreme weather. The case in San Francisco is weighing the question of whether climate change damages connected to the burning of oil are specifically the fault of the companies that extract and sell it.

The judge in People of the State of California v. BP P.L.C. et al. had both the plaintiffs – the cities of Oakland and San Francisco – and the defendants – several major oil companies – answer basic questions about climate change in a tutorial format. Counter to what some might have expected, an oil company lawyer largely confirmed the consensus science on the issue, but challenged the idea that oil companies should be held accountable.

Stanford Report spoke with Katharine Mach, a senior research scientist at the School of Earth, Energy & Environmental Science, and Deborah Sivas, the Luke W. Cole Professor of Environmental Law, to get their perspectives on the climate tutorial, the science in question and the role of the judiciary in confronting climate change challenges. 

Stanford law and science experts discuss court case that could set precedent for climate change litigation by Rob Jordon, Stanford News, Mar 30, 2018 

Links posted on Facebook

Sun Mar 25, 2018

Mon Mar 26, 2018

Tue Mar 27, 2018

Wed Mar 28, 2018

Thu Mar 29, 2018

Fri Mar 30, 2018

Sat Mar 31, 2018

New research, March 19-25, 2018

March 30, 2018 - 7:02am

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

The figure is from paper #80.

Climate change mitigation

1. Unlikely pioneers: creative climate change policymaking in smaller U.S. cities

"I find that local leaders reframe climate change action as a way to save money and attract economic development. Personal environmental ethics drive small town leaders to reduce greenhouse gase emissions. Citizen committees can provide technical resources and political support. Otherwise, and more subtly, citizens can create a political environment that reduces resistance to climate change policymaking."

Emission reductions

2. Healthy, affordable and climate-friendly diets in India

"We show that more than two-thirds of Indians consume insufficient micronutrients, particularly iron and Vitamin A, and to a lesser extent zinc. A greater proportion of urban households than rural households are deficient at all income levels and for all nutrients, with few exceptions. Deficiencies reduce with increasing income. Using constrained optimization, we find that households could overcome these nutrient deficiencies within their food budgets by diversifying their diets, particularly towards coarse cereals, pulses, and leafy vegetables, and away from rice. These dietary changes could reduce India’s agricultural greenhouse gas (GHG) emissions by up to 25%."

3. Life cycle assessment research and application in Indonesia

"The research and application of LCA in Indonesia are still in its infancy, as partly proved by a relatively small number of publications as compared to some other Southeast Asian countries. However, there was a notable increase in publication over the last 5 years, indicating a growing interest in LCA, mainly from academics and to less extent from private sectors."

4. The Convergence of China’s Marginal Abatement Cost of CO2: An Emission-Weighted Continuous State Space Approach

5. Managing cropland and rangeland for climate mitigation: an expert elicitation on soil carbon in California (open access)

6. Greenhouse gas emissions and energy use associated with production of individual self-selected US diets (open access)

7. Analyzing the greenhouse gas impact potential of smallholder development actions across a global food security program (open access)

8. Economic and environmental performance of dryland wheat-based farming systems in a 1.5 °C world

9. Subsidence and carbon dioxide emissions in a smallholder peatland mosaic in Sumatra, Indonesia (open access)

10. Forest loss and Borneo's climate

"We conclude that loss of forest in Borneo has increased local daily temperatures and temperature extremes, and reduced daily precipitation."

Energy production

11. Why is China’s wind power generation not living up to its potential? (open access)

12. Estimating future wood outtakes in the Norwegian forestry sector under the shared socioeconomic pathways

13. An environmental assessment of small hydropower in India: the real costs of dams’ construction under a life cycle perspective

14. Sale of profitable but unaffordable PV plants in Spain: Analysis of a real case

15. How renewable production depresses electricity prices: Evidence from the German market

16. Solar energy's potential to mitigate political risks: The case of an optimised Africa-wide network (open access)

17. A framework for evaluating the current level of success of micro-hydropower schemes in remote communities of developing countries

18. Russian industry responses to climate change: the case of the metals and mining sector

"The Russian government has no plans to phase out coal and is instead actively seeking to expand the coal industry. This highlights the obstacles to Russia’s commitment to climate policy at both the domestic and international levels."

19. Measurement of methane emissions from abandoned oil and gas wells in Hillman State Park, Pennsylvania

20. Benefits and challenges of expanding grid electricity in Africa: A review of rigorous evidence on household impacts in developing countries

21. Views from above: policy entrepreneurship and climate policy change on electricity in the Canadian Arctic

Climate change communication

22. Emotions predict policy support: Why it matters how people feel about climate change

"In two studies, we find that climate scientists (N = 44) experience greater emotional intensity about climate change than do students (N = 94) and the general population (N = 205), and that patterns of emotional responses explain differences in support for climate change policy. Scientists tied their emotional responses to concern about consequences of climate change to future generations and the planet, as well as personal identities associated with responsibility to act. Our findings suggest that “objects of care” that link people to climate change may be crucial to understanding why some people feel more strongly about the issue than others, and how emotions can prompt action."

23. What makes for compelling science? Evidential diversity in the evaluation of scientific arguments

"In both studies, diverse evidence on the geographical and socio-cultural dimension increased perceived support for scientific claims, but the relative impact of these dimensions differed between domains; geographical diversity had a larger effect on claims about climate change; socio-cultural diversity had a larger effect on claims about health. On the temporal dimension, recent non-diverse evidence (i.e. from the same recent period) increased perceived support for scientific claims more than diverse evidence."

24. Community climate change beliefs, awareness, and actions in the wake of the September 2013 flooding in Boulder County, Colorado

25. Multi-hazard weather risk perception and preparedness in eight countries

26. Tipping Points and Climate Change: Metaphor Between Science and the Media (open access)

27. Believing in climate change, but not behaving sustainably: Evidence from a one-year longitudinal study

"Cluster membership predicted different outcomes: the “Highly Concerned” were most supportive of government climate policies, but least likely to report individual-level actions, whereas the “Skeptical” opposed policy solutions but were most likely to report engaging in individual-level pro-environmental behaviors."

28. Information and coercive regulation: The impact of fuel mix information disclosure on states’ adoption of renewable energy policy

29. Attributes of weathercasters who engage in climate change education outreach

30. The influence of political leaders on climate change attitudes

"Our experiments reveal that survey respondents take different positions on climate change policy when they learn what positions leaders hold. When respondents learn that leaders take divergent positions on addressing climate change, they become more polarized along party lines. But when leaders converge on a policy proposal, they also bring those who follow them into closer agreement, providing evidence that partisan polarization at the mass level can be overcome when leaders come together on environmental policies."

Climate change

Temperature, precipitation, and wind

31. Diurnal Cycle of Rainfall and Winds near the South Coast of China

32. Impacts of climate change on the trends of extreme rainfall indices and values of maximum precipitation at Olimpiyat Station, Istanbul, Turkey

33. Variability of thermal and precipitation conditions in the growing season in Poland in the years 1966–2015 (open access)

34. How well can we correct systematic errors in historical XBT data?

Extreme events

35. Impact of aerosols on tropical cyclone-induced precipitation over the mainland of China

36. Sustainable livelihoods and effectiveness of disaster responses: a case study of tropical cyclone Pam in Vanuatu

"While aid agencies actively responded during and after Pam, local people too responded to the event with strategies based on livelihoods diversification, food security techniques, traditional knowledge and cooperation intra- and inter-communities. The study emphasizes the need for an integrative approach where disaster responses from the top-down integrate that from the bottom-up."

37. Northern Hemisphere extratropical winter cyclones variability over the 20th century derived from ERA-20C reanalysis

38. Increased wind risk from sting-jet windstorms with climate change (open access)

39. Tornado seasonality in the southeastern United States

40. The 2010 Pakistan floods in a future climate

"In the model context, these precipitation increases are substantial with 50–100% increases in rainfall rates. This implies that the future equivalent of the 2010 Pakistan floodings may have even stronger socio-economic impacts."

41. Thunderstorm climatology in the Mediterranean using cloud-to-ground lightning observations

42. Increase in extreme precipitation events under anthropogenic warming in India (open access)

Forcings and feedbacks

43. The influence of non-CO 2 forcings on cumulative carbon emissions budgets

44. Homogenization and trend analysis of the 1958-2016 in-situ surface solar radiation records in China

"The homogenized data show that the national average SSR has been declining significantly over the period 1958-1990; this dimming trend mostly diminished over the period 1991-2005 and was replaced by a brightening trend in the recent decade."

45. Aerosol optical depth in the European Brewer Network (open access)

46. Primary and secondary organic aerosols in summer 2016 in Beijing (open access)

47. Religious burning as a potential major source of atmospheric fine aerosols in summertime Lhasa on the Tibetan Plateau (open access)

48. Marine aerosol distribution and variability over the pristine Southern Indian Ocean

49. The observed relationship of cloud to surface longwave radiation and air temperature at Ny-Ålesund, Svalbard (open access)

50. Tibetan Plateau impacts global dust transport in the upper troposphere


51. Changes in Andes snow cover from MODIS data, 2000–2016 (open access)

52. Snow cover and snow albedo changes in the central Andes of Chile and Argentina from daily MODIS observations (2000–2016)

53. The snow load in Europe and the climate change (open access)

54. Characteristics of Eurasian snowmelt and its impacts on the land surface and surface climate

55. Meltwater storage in low-density near-surface bare ice in the Greenland ice sheet ablation zone (open access)

"We present measurements of ice density that show the melting bare-ice surface of the Greenland ice sheet study site is porous and saturated with meltwater. The data suggest up to 18 cm of meltwater is temporarily stored within porous, low-density ice. The findings imply meltwater drainage off the ice sheet surface is delayed and that the surface mass balance of the ice sheet during summer cannot be estimated solely from ice surface elevation change measurements."

56. Modelling seasonal meltwater forcing of the velocity of land-terminating margins of the Greenland Ice Sheet (open access)

57. Glacier mass balance in the Qinghai–Tibet Plateau and its surroundings from the mid-1970s to 2000 based on Hexagon KH-9 and SRTM DEMs

Carbon cycle

58. Arctic Ocean CO2 uptake: an improved multiyear estimate of the air–sea CO2 flux incorporating chlorophyll a concentrations (open access)

"The uncertainty in the CO2 flux estimate was reduced, and a net annual Arctic Ocean CO2 uptake of 180 ± 130 Tg C y−1 was determined to be significant."

59. Uncertainty in the global oceanic CO2 uptake induced by wind forcing: quantification and spatial analysis (open access)

Climate change impacts


60. The unprecedented 2014 Legionnaires’ disease outbreak in Portugal: atmospheric driving mechanisms

61. Climate Change Could Increase the Geographic Extent of Hendra Virus Spillover Risk (open access)

"In response to climate change, risk expanded southwards due to an expansion of P. alecto suitable habitat, which increased the number of horses at risk by 175–260% (110,000–165,000). In the northern limits of the current distribution, spillover risk was highly uncertain because of model extrapolation to novel climatic conditions. The extent of areas at risk of spillover from P. conspicillatus was predicted shrink. Due to a likely expansion of P. alecto into these areas, it could replace P. conspicillatus as the main HeV reservoir."

62. Temporal trends in human vulnerability to excessive heat (open access)

63. Scenarios for adaptation and mitigation in urban Africa under 1.5 °C global warming

64. Modeling environmentally mediated rotavirus transmission: The role of temperature and hydrologic factors

65. Evolution of rain and photoperiod limitations on the soybean growing season in Brazil: The rise (and possible fall) of double-cropping systems

66. Harvested area gaps in China between 1981 and 2010: effects of climatic and land management factors (open access)

67. Adaptation as a political arena: Interrogating sedentarization as climate change adaptation in Central Vietnam

68. Humid heat stress affects trained female athletes more than does their menstrual phase

69. Can we use crop modelling for identifying climate change adaptation options?


70. Carbon–climate feedbacks accelerate ocean acidification (open access)

"We show climate–carbon feedbacks accelerate and enhance ocean acidification. Such an acceleration of ocean acidification may further undermine the ability of marine biota to adapt to the changing environment."

71. Spatial heterogeneity of the relationship between vegetation dynamics and climate change and their driving forces at multiple time scales in Southwest China

72. Water availability is more important than temperature in driving the carbon fluxes of an alpine meadow on the Tibetan Plateau

73. Snow cover phenology affects alpine vegetation growth dynamics on the Tibetan Plateau: Satellite observed evidence, impacts of different biomes, and climate drivers

74. Productivity of an Australian mountain grassland is limited by temperature and dryness despite long growing seasons

75. Leaf phenology paradox: Why warming matters most where it is already warm

"We found spring green-up is faster in the mountains, while coastal forests express a larger sensitivity to inter-annual temperature anomalies. Despite our detection of a decreasing trend in sensitivity to warming with temperature in all regions, we identified an ecosystem interaction: Deciduous dominated forests are less sensitive to warming than are those with fewer deciduous trees, likely due to the continuous presence of leaves in evergreen species throughout the season. Mountainous forest green-up is more susceptible to intensifying drought and moisture deficit, while coastal areas are relatively resilient. We found that with increasing canopy thermal stress, defined as canopy-air temperature difference, leaf development slows following dry years, and accelerates following wet years."

76. Post-1980 shifts in the sensitivity of boreal tree growth to North Atlantic Ocean dynamics and seasonal climate: Tree growth responses to North Atlantic Ocean dynamics

77. Higher absorbed solar radiation partly offset the negative effects of water stress on the photosynthesis of Amazon forests during the 2015 drought (open access)

78. Unravelling the adaptation strategies employed by Glaciozyma antarctica PI12 on Antarctic sea ice

Other papers

General climate science

79. A Paper on the Tropical Intraseasonal Oscillation Published in 1963 in a Chinese Journal (open access)

80. NASA's Black Marble nighttime lights product suite (open access)


81. A chironomid-based record of temperature variability during the past 4000 years in northern China and its possible societal implications (open access)

82. Two-step human–environmental impact history for northern New Zealand linked to late-Holocene climate change

83. Multi-proxy evidence for an arid shift in the climate and vegetation of the Banni grasslands of western India during the mid- to late-Holocene

Environmental issues

84. Development of Landsat-based annual US forest disturbance history maps (1986–2010) in support of the North American Carbon Program (NACP)

85. Observational analyses of dramatic developments of a severe air pollution event in the Beijing area (open access)