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Climate Hustle

Explaining climate change science & rebutting global warming misinformation

Scientific skepticism is healthy. Scientists should always challenge themselves to improve their understanding. Yet this isn't what happens with climate change denial. Skeptics vigorously criticise any evidence that supports man-made global warming and yet embrace any argument, op-ed, blog or study that purports to refute global warming. This website gets skeptical about global warming skepticism. Do their arguments have any scientific basis? What does the peer reviewed scientific literature say?


Donald Trump wants to build a wall – to save his golf course from global warming

Posted on 26 May 2016 by dana1981

Donald Trump has consistently expressed his conspiratorial and misinformed beliefs that global warming is a hoax.

Ice storm rolls from Texas to Tennessee - I'm in Los Angeles and it's freezing. Global warming is a total, and very expensive, hoax!

Trump is also the presumptive Republican Party nominee for president in 2016, and were he elected, would be the leader of the country with the second-highest net carbon pollution in the world. These are frightening thoughts.

However, as reported by Politico, Trump acknowledges the reality and threats posed by human-caused global warming when it comes to protecting his own assets, and in keeping with his affinity for building walls:



In-depth: Experts assess the feasibility of ‘negative emissions’

Posted on 25 May 2016 by Guest Author

This is a re-post from Carbon Brief

To limit climate change to “well below 2C”, as nationsagreed to do in Paris last December, modelling shows it is likely that removing carbon dioxide emissions from the atmosphere later on this century will be necessary.
Scientists have imagined a range of “negative emissions” technologies, or NETs, that could do just that, asexplained by Carbon Brief yesterday. But are any of them realistic in practice?

Carbon Brief reached out to a number of scientists, policy experts and campaigners who have studied both the necessity and feasibility of negative emissions.

We sent them the following identical email:

The Paris Agreement calls for “holding the increase in the global average temperature to well below 2C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5C above pre-industrial levels”. However, as the IPCC AR5 report showed, the majority of modelling to date assumes a significant global-scale deployment of negative emissions technologies in the second half of this century, if such temperature limits are to be achieved.
1) What negative emissions technologies offer the most promise – and why?
2) Is it feasible to achieve the scale of deployment required to meet the aims of the Paris Agreement? If so, how? If not, why?

These are the responses we received, first as sample quotes, then, below, in full:

  • Ottmar Edenhofer, Intergovernmental Panel on Climate Change – “Whether we can achieve the deployment needed for the aims declared in Paris last year…depends very much on which negative emissions options will end up to be at our disposal ultimately.”
  • Detlef van Vuuren, PBL Netherlands Environmental Assessment Agency – “At the moment, BECCS and large-scale reforestation seem to be most promising based on a combination of technology-readiness, costs, and potential. At the same time, both options are not without challenges.”
  • David Keith, Harvard University – “I am skeptical that BECCS should be used beyond narrow niches…Instead, I would focus on accelerated weathering and air capture which could, in principle, be scaled to many gigatonnes per year with low land footprint.”
  • David MacKay, former chief DECC scientist – “Do I think it is a realistic view of what the world will do? No, not at the moment, because I think the Paris discussions completely ducked this issue, which is one of the most important issues out there.”
  • Pete Smith, University of Aberdeen – “For BECCS, there are significant issues with competition for land if it is implemented at the median rate projected by integrated assessment models, and water use is also significant.”
  • Oliver Geden, German Institute for International and Security Affairs – “A strategic debate about how to use carbon dioxide removal within a broader portfolio of climate policy measures is clearly lacking.”
  • Hannah Mowat, Fern – “If countries reduce emissions fast enough, then the level of CO2 that must be removed is entirely feasible, and, if done through [forest] restoration, can be positive.”
  • Rob Bailey, Chatham House – “It is clearly less risky not to emit a tonne of CO2 in the first place, than to emit one in expectation of being able to sequester it for an unknown period of time, at unknown cost, with unknown consequences, at an unknown date and place in the future.”
  • Joeri Rogelj, International Institute for Applied Systems Analysis – “Without CO2 emissions being penalised or strongly discouraged in some way, a large-scale deployment does never seem realistic.”
  • Stephan Singer, WWF – “A debate on the Paris objectives must not start with ‘negative emissions’, since this might be used to delay actions towards later decades.”
  • Sabine Fuss, Mercator Research Institute – “There is no champion to be singled out here and we will have to look for the portfolio of negative emissions technologies that minimises unwanted effects on non-climate policy goals.”
  • John Lanchbery, RSPB – “A large proportion, if not all of this, could probably be achieved by the conservation and enhancement of natural forests, peatlands and other natural sinks and reservoirs – without recourse to negative emissions technologies.”
  • Glen Peters, CICERO – “The best carbon dioxide removal strategy would be to use a mix of technologies, with each technology located to avoid its limitations.”
  • Noah Deich, Centre for Carbon Removal – “We must engage the diverse set of stakeholders that will develop and deploy carbon removal systems today to ensure we can meet tomorrow’s climate, economic, and social goals.”
  • Mike Childs, Friends of the Earth – “Critically, use of land always brings issues of land rights and justice. It would be a disaster to see poor communities thrown of their land for negative emissions — land grabs are well documented for biofuels.”
  • Florian Kraxner, International Institute for Applied Systems Analysis – “Biomass co-firing with existing retrofitted or newly built coal power plants seems to be an easy entry for the BECCS technology since it is an expensive technology and economy of scale is key.”
  • Sami Yassa, Natural Resources Defense Council –“There is no scientific basis for assuming that BECCS can deliver “negative emissions” after accounting for direct and indirect life-cycle emissions.”
  • Tim Lenton, University of Exeter – “We can start on this now, at low cost, and as part of already internationally signed-up-to targets under the Bonn Challenge and subsequent New York Declaration.”



Tracking the 2°C Limit - April 2016

Posted on 24 May 2016 by Rob Honeycutt

April is starting to come down off the shockingly high anomalies of the first couple of months of this year. GISS is clocking in a still strong warm anomaly of 1.11°C. This is by far the hottest April in the record, beating the previous April record in 2010 by a full 0.24°C. (Full size graph.)

The Ocean Nino Index is continuing to fall and model expectations are forecasting La Niña later in the year. The satellite data in both the RSS and UAH data fell slightly from last month but I'd expect next month to pop back up just a touch, if past data is any indication. (Full size graph.)



Climate denial arguments fail a blind test

Posted on 23 May 2016 by dana1981

As we saw in the recent legal ruling against Peabody coal, arguments and myths that are based in denial of the reality of human-caused global warming rarely withstand scientific scrutiny.

In a new study published in Global Environmental Change, a team led by Stephen Lewandowsky tested the accuracy of some popular myths and contrarian talking points sampled from climate denial blogs and other media outlets. The scientists searched the blogs for key words related to Arctic sea ice, glaciers, sea level rise, and temperature to identify the most popular arguments. Not surprisingly, they found some common myths:

nearly two-thirds of all mentions of temperature on the three top contrarian blogs included a claim of “cooling”; and likewise more than a quarter of all mentions of arctic ice alluded to its “recovery”, and so on.

Using their search results, the authors put together language that was representative of the most common arguments made on the climate denial blogs about these subjects. To ensure that their example arguments accurately depicted contrarian claims and rhetorical techniques, they also consulted climate experts, who confirmed their representativeness. Interestingly, the climate experts identified many of the same mistakes that my colleagues and I found in our 2015 study attempting to replicate climate contrarian research (cherry picking data, for example).

The authors then used the same data and arguments as the contrarian blogs, but changed the climate variables to something related to economics, and presented them to economists and statisticians:

For example, the [glaciers] scenario pairs the claim that “our country’s rural population is growing, not shrinking” with a figure that showed the change in population for numerous individual villages, akin to a figure depicting the mass balance of individual glaciers.

In addition, an alternative statement was constructed for each scenario that summarized the mainstream scientific interpretation of the climate data, again translated into economic or demographic terms (e.g., “almost all of the rural regions of the country are losing population”).

The tests involved common contrarian myths that:



2016 SkS Weekly Digest #21

Posted on 22 May 2016 by John Hartz

SkS Highlights... El Niño to La Niña... Toon of the Week... Quote of the Week... He Said What?... SkS in the News... SkS Spotlights... Coming Soon on SkS... Poster of the Week... SkS Week in Review... 97 Hours of Consensus...

SkS Highlights

Lord Krebs: scientists must challenge poor media reporting on climate change by John Krebs (The Conversation UK) attracted the highest number of comments of the articles posted on SkS during the past week. What Sir David King gets wrong about carbon pricing by Judy Hindley and Brian Utton (Climate Consensus - the 97%, Guardian) drew the second highest number of comments. 

El Niño to La Niña

One of the strongest El Niños on record has been dominating the tropical Pacific Ocean for the past year. But beneath the surface, a deep pool of cool water has been sliding slowly eastward for the past couple of months. This massive, slow-motion wave is a favorable sign that La Niña—the cool phase of the ENSO climate pattern—might develop. 

La Niña coming? Deep pool of cool water is making its way across tropical Pacific by Rebecca Lindsey, (NOAA), May 16, 2016

Toon of the Week

2016 Toon 21 



2016 SkS Weekly News Roundup #21

Posted on 21 May 2016 by John Hartz

A chronological listing of the news articles posted on the Skeptical Science Facebook page during the past week.

Sun May 15



Lord Krebs: scientists must challenge poor media reporting on climate change

Posted on 20 May 2016 by Guest Author

John Krebs, University of Oxford

Ocean acidification is causing fundamental and dangerous changes in the chemistry of the world’s oceans yet only one in five Britons has even heard of ocean acidification, let alone believes it a cause for concern. Around 97% of climate scientists believe global warming is principally driven by human activity, yet only 16% of the public know the expert consensus to be this strong.

These are just two examples of common misconceptions among the UK public on the science of climate change. When surveyed, many people report feeling unsure and confused about various aspects of the discipline. Furthermore, they lack trust in scientists: in the wake of the IPCC’s fifth assessment report, nearly four in ten people felt that scientists were exaggerating concerns.

Are these realities any surprise when we see headlines such as “Planet is not overheating, says professor” and “Scientists ‘are exaggerating carbon threat to marine life’” in the UK’s national media? It was the former article that recently prompted a number of members of the House of Lords, including me, to write a letter to the editor of The Times, John Witherow. We highlighted the newspaper’s recent record of tendentious and misleading coverage of climate science (among many other articles, it must be said, that are worthy of the paper’s name and tradition).

The “not overheating” article described a study suggesting there is no statistically valid evidence for man-made climate change – and therefore that the planet will not warm significantly by the end of the century. But the study was not conducted by a climate scientist and it ignored basic physical laws. It did not undergo scientific peer-review and it was funded by a climate-sceptic lobby group, the Global Warming Policy Foundation.

The fact that a newspaper of The Times’ standing gave coverage to such a piece of research is both remarkable and deeply concerning. But it is not an isolated example. Instead it typifies a disturbing pattern in parts of the UK national media where there is an apparent determination to systematically undermine climate science and those conducting it – and to amplify marginal dissenting arguments even when they come with no evidence.

Overheating? 2015 was actually the hottest year on record. Met Office, CC BY-NC-SA



Climate scientists, mourning Earth's losses, should make their voices heard

Posted on 19 May 2016 by Guest Author

Sarah Myhre is an ocean and climate scientist with expertise in the marine ecological consequences of abrupt climate warming.

It’s easy to find a news hook to begin an opinion piece on climate change. Coral bleaching, record-setting heat waves, and expensive, deadly wildfires are a weekly occurrence in the news cycle. But, as climate warming advances, extreme events won’t be newsworthy – they’ll be expected.

We scientists are the gatekeepers of the basic information that fuels decision making by nations, businesses and communities. As these public entities are more and more threatened by the advancing impacts of climate warming, from flooding, to water scarcity, to the spread of tropical diseases, our role as objective scientists has to change. We are so skilled at many, many detailed and quantitative tasks, but, as you would expect from a community of introverts, we are not great at shining that brilliant light back on ourselves.

Earth scientists, who are teaching, or researching, abut a silent, uncertain, and painful threshold. This is the threshold where climate change shifts from being about science and quantification to being about loss and the suffering of others.

For example, my 90-year-old grandmother, who lives in a low-income assisted care facility, suffers greatly when the new heat waves roll across the Pacific Northwest in June, July and August (and now May this year). Heat is deadly to seniors – this isn’t an issue of comfort, it’s an issue of safety. I tell myself, every time I leave her home, that I have to do something. I think of all the other grandmothers and great-grandmothers suffering in silence. I feel the cognitive dissonance, as I drive my Honda home, and the pain of it wells into the palms of my hands and the back of my mouth.

The problem is, we are past the threshold – we are just playing games with ourselves. In the anticipation of it, it has passed silently underneath our feet. We are already committed to a world that is warmer and more dangerous than the world of my grandmother’s childhood. That world – where we had time, we didn’t have to be political, we took only small, calculated risks – has evaporated in front of us. So, why are we still operating under old rules?

One reason may be that scientists are naturally risk-averse where it comes to public dialogue.



Ocean Oxygen – another climate shoe dropping

Posted on 18 May 2016 by howardlee

How warming temperatures and ocean acidification are recreating an ancient killer

Ocean anoxia – widespread oxygen-starved dead zones in oceans - did the killing of ocean life in several mass extinctions of Earth’s past.  Anoxia went hand-in-hand with CO2 emissions, rising global temperatures, and (often) ocean acidification, a situation which today’s climate change is recreating with uncanny likeness.

Atmospheric oxygen levels are declining as a result of burning fossil fuels, but that’s not the cause of ocean anoxia. Neither are we at risk from asphyxiation, because the oxygen decline is at a rate of about 4 parts per million (ppm) per year, compared to an atmospheric oxygen concentration of 21% (ie 210,000 ppm). It would take nearly 4,000 years of burning fossil fuels at current rates before atmospheric oxygen declined to unsafe levels!

Even in normal, healthy oceans, dissolved oxygen levels in middle-depth waters (between about 500 to 1,500 meters) are low enough to discourage most higher animals. This makes those depths an important refuge for krill and other prey species to hang out during the day, safe from visual predators. In the dark of night, these creatures venture nearer the surface to graze on plankton, an impressive commute given their small size.

Dissolved oxygen in depth slices through our oceans

Depth slices through the oceans showing how dissolved oxygen declines from the surface to middle depths and then rises again in deep water. Constructed from World Ocean Atlas 2013.

There are places around the world where these oxygen minimum zones are much shallower than elsewhere, and there are also coasts where polluted river water delivers excess nutrients into the sea, causing coastal dead zones, for example in the Gulf of Mexico. But these pale in comparison to times in Earth’s past when ocean anoxia became so intense and widespread that it contributed to the permanent annihilation of many marine species. But if we look at the conditions that led to past “Ocean Anoxic Events” (OAEs), and compare them to our altered climate in the coming decades, the parallels are sobering.

How it works:



What Sir David King gets wrong about carbon pricing

Posted on 17 May 2016 by Guest Author

Judy Hindley is a writer and long-term activist, co-founder of Marlborough Climate Pledge and Citizens’ Climate Lobby UK. Brian Utton is the national coordinator of Citizens’ Climate Lobby UK.

Sir David King, UK Special Representative for Climate Change, recently took to The Guardian to throw cold water on the prospects of carbon pricing as an effective tool for reducing greenhouse gas emissions. He instead advocated for increased government research funding to develop ‘competitive’ clean alternatives to fossil fuels.

There can be little argument that swift, effective action on the climate is essential. In the UK alone, the Department for Environment, Food and Rural Affairs’ most recent Climate Change Risk Assessment projects a potential doubling of people at significant flood risk between 2012 and the 2020s, and industry experts warned that the economic costs of this last winter’s storms was over £5 billion.

Yes, it’s true that the current pricing regime can be described as – at best - ‘sluggish’. A landmark report by the Institute of Fiscal Studies in 2013 described the system of UK taxes of recent years as “complex and incoherent and less effective than it could be at reducing carbon emissions at the lowest overall cost”. A key component, the EU’s Emissions Trading Scheme has suffered from an excess of free allowances, fraudulent activity in the market, end-use monitoring that misses most emissions, and administrative complexity most countries cannot fully implement.

The IFS called instead for a single, consistent carbon price, leveled upstream.



Explainer: 10 ways ‘negative emissions’ could slow climate change

Posted on 16 May 2016 by Guest Author

This is a re-post from Carbon Brief

Ten options for negative emissions, by Rosamund Pearce for Carbon Brief

The Paris Agreement, adopted at the COP21 climate talks in December, sets out a global aim to limit average global surface temperatures to “well below 2C” above pre-industrial levels. It adds that there should be “efforts” to limit it to 1.5C.

But as countries across the world move towards signing and ratifying the agreement, there remains the key question of how these ambitious targets can be met.

 study published last year warned that all the scenarios for keeping global temperature rise to 2C require “negative emissions” – removing CO2 from the atmosphere and storing it on land, underground or in the oceans.

Although plenty of negative emissions technologies have been proposed, none are ready to be rolled out around the world, or, in some cases, even demonstrated to work at scale.

Kicking off a week-long series on negative emissions technologies (NETs), Carbon Brief takes a look at the many and varied options. Tomorrow, we will publishthe views of a wide range of experts who have examined the feasibility of NETs.



2016 SkS Weekly Digest #20

Posted on 15 May 2016 by John Hartz

SkS Highlights... El Niño to La Niña... Toon of the Week... Quote of the Week... He Said What?... SkS in the News... SkS Spotlights... Coming Soon on SkS... Poster of the Week... SkS Week in Review... 97 Hours of Consensus...

SkS Highlights

On May 6, the National Center for Science Education (NCSE) announced the winners of its Friend of the Planet award for 2016: Katharine Hayhoe of Texas Tech University; Dana Nuccitelli and John P. Abraham, authors of the Climate Consensus – the 97% column hosted on the Guardian newspaper; and Skeptical Science, a website devoted to explaining climate change science and rebutting global warming misinformation created and maintained by John Cook of the University of Queensland.

"All of the Friends of the Planet for 2016 shine as climate communicators, in different but complementary ways," NCSE Executive Director Ann Reid explained. "Katharine Hayhoe excels at building connections between science and society and Dana Nuccitelli and John Abraham have consistently provided timely commentary on the latest developments. And Skeptical Science is simply unrivaled as a vast, up-to-date, and in-depth source of accurate and accessible information on climate change science."

Friend of Darwin and Friend of the Planet awards for 2016, National Center for Science Education (NCSE) news release, May 9, 2016 

El Niño to La Niña

There’s a 75% chance that La Niña will be in place by the fall, meaning sea surface temperatures in the central Pacific at the equator will be more than 0.5°C below average. It’s possible the transition from El Niño to La Niña will be quick, with forecasters slightly favoring La Niña developing this summer. What’s behind this reasonably confident forecast

May 2016 El Niño/La Niña update: Switcheroo! by Emily Becker, (NOAA), May 11, 2016

Toon of the Week

 2016 Toon 20



2016 SkS Weekly News Roundup #20

Posted on 14 May 2016 by John Hartz

A chronological listing of the news articles posted on the Skeptical Science Facebook page during the past week.

Sun May 8



The things people ask about the scientific consensus on climate change

Posted on 12 May 2016 by John Cook

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

It’s been almost a month since the paper I co-authored on the synthesis of research into the scientific consensus on climate change was published. Surveying the many studies into scientific agreement, we found that more than 90% of climate scientists agree that humans are causing global warming.

It’s a topic that has generated much interest and discussion, culminating in American Democrat Senator Sheldon Whitehouse highlighting our study on the US Senate floor this week.

My co-authors and I even participated in an Ask Me Anything (AMA) session on the online forum Reddit, answering questions about the scientific consensus.

While my own research indicates that explaining the scientific consensus isn’t that effective with those who reject climate science, it does have a positive effect for people who are open to scientific evidence.

Among this “undecided majority”, there was clearly much interest with the session generating 154,000 page views and our AMA briefly featuring on the Reddit homepage (where it was potentially viewed by 14 million people).

Here is an edited selection of some of the questions posed by Reddit readers and our answers.

Q: Why is this idea of consensus so important in climate science? Science isn’t democracy or consensus, the standard of truth is experiment.

If this were actually true, wouldn’t every experiment have to reestablish every single piece of knowledge from first principles before moving on to something new? That’s obviously not how science actually functions.

Consensus functions as a scaffolding allowing us to continue to build knowledge by addressing things that are actually unknown.

Q: Does that 97% all agree to what degree humans are causing global warming?

Different studies use different definitions. Some use the phrase “humans are causing global warming” which carries the implication that humans are a dominant contributor to global warming. Others are more explicit, specifying that humans are causing most global warming.

Within some of our own research, several definitions are used for the simple reason that different papers endorse the consensus in different ways. Some are specific about quantifying the percentage of human contribution, others just say “humans are causing climate change” without specific quantification.

We found that no matter which definition you used, you always found an overwhelming scientific consensus.



CO2's Role in Global Warming Has Been on the Oil Industry's Radar Since the 1960s

Posted on 12 May 2016 by Guest Author

This is a re-post from Inside Climate News

The oil industry's leading pollution-control consultants advised the American Petroleum Institute in 1968 that carbon dioxide from burning fossil fuels deserved as much concern as the smog and soot that had commanded attention for decades.

Carbon dioxide was "the only air pollutant which has been proven to be of global importance to man's environment on the basis of a long period of scientific investigation," two scientists from the Stanford Research Institute (SRI) told the API.

This paperalong with scores of other publications, shows that the risks of climate change were being discussed in the inner circles of the oil industry earlier than previously documented. The records, unearthed from archives by a Washington, D.C. environmental law organization, the Center for International Environmental Law (CIEL), reveal that the carbon dioxide question—an obscure corner of research for much of the 20th century—had been closely studied since the 1950s by some oil company researchers.

By the 1960s, the CO2 problem was gaining wider scientific recognition, especially as President Lyndon B. Johnson's science advisers and leading experts brought it to the attention of the White House in 1965.

"If CO2 levels continue to rise at present rates, it is likely that noticeable increases in temperature could occur," SRI scientists Elmer Robinson and R.C. Robbins wrote in their 1968 paper to API.

"Changes in temperature on the world-wide scale could cause major changes in the earth's atmosphere over the next several hundred years including change in the polar ice caps."

Ten years later, the world's leading oil company, Exxon, would launch an ambitious in-house research program into the emerging science of climate change, as detailed by InsideClimate News last year in an investigative series. Beginning in 1978, Exxon researchers hoped their work would identify the risks climate change posed to the company's business and earn it a seat at the table when policymakers moved to limit CO2 emissions, according to internal documents. By the late 1980s, the company and its allies would instead challenge the scientific basis for strong action on climate change.

In a new series of articles, ICN begins to examine how the industry confronted pollution concerns during the infancy of climate research in the mid-20th century. It is based on hundreds of public documents assembled by CIEL, along with others gathered by ICN.

The documents trace early academic research into rising carbon dioxide levels. They show how the oil industry monitored that published work, and help explain the beginnings of its own research. They also show how industry's reaction to mid-century regulation to curtail other forms of air pollution, such as smog, helped shape its approach toward the risks of carbon dioxide.



Coal made its best case against climate change, and lost

Posted on 11 May 2016 by dana1981

Peabody Energy, the world’s largest private sector coal company (now bankrupt), recently faced off against environmental groups in a Minnesota court case. The case was to determine whether the State of Minnesota should continue using its exceptionally low established estimates of the ‘social cost of carbon’, or whether it should adopt higher federal estimates. 

The social cost of carbon is an estimate of how much the damages from carbon pollution cost society via climate change damages. In theory, it represents how much the price of fossil fuels should increase to reflect their true costs.

The coal company called forth witnesses that represented the fringe 2–3% of experts who reject the consensus that humans are the primary cause of global warming, including Roy Spencer and Richard Lindzen, while their opposition invited witnesses like Andrew Dessler and John Abraham who represent the 97% expert consensus.

John Abraham previously summarized the proceedings and ruling in favor of the higher carbon cost estimates, but it’s worth delving into some of the details of the climate science and economics arguments to see why the judge ruled against the coal company and its contrarian witnesses. The losing case from the coal company witnesses (rebutted by John Abraham here and here) can be summarized as follows:



Skeptical Science wins 2016 NCSE Friend of the Planet award

Posted on 10 May 2016 by Guest Author

This is a re-post from NCSE

FOP award

NCSE is pleased to announce the winners of the Friend of Darwin award for 2016: Andrew J. Petto, a physical anthropologist, who formerly served on NCSE's board of directors and as the editor of Reports of the National Center for Science Education; Donald R. Prothero, a paleontologist and prolific author whose latest book is The Story of Life in 25 Fossils; and Paula Spence, a cartoonist and artist who has been contributing graphics of all sorts to NCSE for almost a decade.

"Anj Petto served NCSE, as well as the cause of science education, so long and so well that he was a natural choice," commented NCSE's executive director Ann Reid, "while it would be hard to think of anyone who has contributed as much to the public understanding of the paleontological evidence for evolution and against creationism as Don Prothero." She added, "And Paula Spence's art for NCSE has entertained, enlightened, and educated thousands of people."

NCSE is also pleased to announce the winners of the Friend of the Planet award for 2016: Katharine Hayhoe of Texas Tech University; Dana Nuccitelli and John P. Abraham, who contribute the Climate Consensus – the 97% column to the Guardian; and Skeptical Science, a website devoted to explaining climate change science and rebutting global warming misinformation created and maintained by John Cook of the University of Queensland.

"All of the Friends of the Planet for 2016 shine as climate communicators, in different but complementary ways," Reid explained. "Katharine Hayhoe excels at building connections between science and society and Dana Nuccitelli and John Abraham have consistently provided timely commentary on the latest developments. And Skeptical Science is simply unrivaled as a vast, up-to-date, and in-depth source of accurate and accessible information on climate change science."

The Friend of Darwin and Friend of the Planet awards are presented annually to a select few whose efforts to support NCSE and advance its goal of defending the teaching of evolution and climate science have been truly outstanding. Previous recipients of the Friend of Darwin award include Niles Eldredge, Susan Epperson, John F. Haught, and the plaintiffs in Kitzmiller v. Dover. Previous recipients of the Friend of the Planet Award include Michael Mann, Naomi Oreskes, and the Alliance for Climate Education.



Comparing models to the satellite datasets

Posted on 9 May 2016 by Guest Author

This is a re-post from Gavin Schmidt at RealClimate

How should one make graphics that appropriately compare models and observations? There are basically two key points (explored in more depth here) – comparisons should be ‘like with like’, and different sources of uncertainty should be clear, whether uncertainties are related to ‘weather’ and/or structural uncertainty in either the observations or the models. There are unfortunately many graphics going around that fail to do this properly, and some prominent ones are associated with satellite temperatures made by John Christy. This post explains exactly why these graphs are misleading and how more honest presentations of the comparison allow for more informed discussions of why and how these records are changing and differ from models.

The dominant contrarian talking point of the last few years has concerned the ‘satellite’ temperatures. The almost exclusive use of this topic, for instance, in recent congressional hearings, coincides (by total coincidence I’m sure) with the stubborn insistence of the surface temperature data sets, ocean heat content, sea ice trends, sea levels, etc. to show continued effects of warming and break historical records. To hear some tell it, one might get the impression that there are no other relevant data sets, and that the satellites are a uniquely perfect measure of the earth’s climate state. Neither of these things are, however, true.

The satellites in question are a series of polar-orbiting NOAA and NASA satellites with Microwave Sounding Unit (MSU) instruments (more recent versions are called the Advanced MSU or AMSU for short). Despite Will Happer’s recent insistence, these instruments do not register temperatures “just like an infra-red thermometer at the doctor’s”, but rather detect specific emission lines from O2 in the microwave band. These depend on the temperature of the O2 molecules, and by picking different bands and different angles through the atmosphere, different weighted averages of the bulk temperature of the atmosphere can theoretically be retrieved. In practice, the work to build climate records from these raw data is substantial, involving inter-satellite calibrations, systematic biases, non-climatic drifts over time, and perhaps inevitably, coding errors in the processing programs (no shame there – all code I’ve ever written or been involved with has bugs).

Let’s take Christy’s Feb 16, 2016 testimony. In it there are four figures comparing the MSU data products and model simulations. The specific metric being plotted is denoted the Temperature of the “Mid-Troposphere” (TMT). This corresponds to the MSU Channel 2, and the new AMSU Channel 5 (more or less) and integrates up from the surface through to the lower stratosphere. Because the stratosphere is cooling over time and responds uniquely to volcanoes, ozone depletion and solar forcing, TMT is warming differently than the troposphere as a whole or the surface. It thus must be compared to similarly weighted integrations in the models for the comparisons to make any sense.

The four figures are the following:


There are four decisions made in plotting these graphs that are problematic:

  • Choice of baseline,
  • Inconsistent smoothing,
  • Incomplete representation of the initial condition and structural uncertainty in the models,
  • No depiction of the structural uncertainty in the satellite observations.

Each of these four choices separately (and even more so together) has the effect of making the visual discrepancy between the models and observational products larger, misleading the reader as to the magnitude of the discrepancy and, therefore, it’s potential cause(s).

To avoid discussions of the details involved in the vertical weighting for TMT for the CMIP5 models, in the following, I will just use the collation of this metric directly from John Christy (by way of Chip Knappenburger). This is derived from public domain data (historical experiments to 2005 and RCP45 thereafter) and anyone interested can download it here. Comparisons of specific simulations for other estimates of these anomalies show no substantive differences and so I’m happy to accept Christy’s calculations on this. Secondly, I am not going to bother with the balloon data to save clutter and effort; None of the points I want to make depend on this.

In all that follows, I am discussing the TMT product, and as a shorthand, when I say observations, I mean the observationally-derived TMT product. For each of the items, I’ll use the model ensemble to demonstrate the difference the choices make (except for the last one), and only combine things below.



2016 SkS Weekly Digest #19

Posted on 8 May 2016 by John Hartz

SkS Highlights... El Niño Impacts... Toon of the Week... Quote of the Week... He Said What?... SkS in the News... SkS Spotlights... Coming Soon on SkS... Poster of the Week... SkS Week in Review... 97 Hours of Consensus...

SkS Highlights

Using the metric of the number of comments garnered, the following articles were the most popular of those posted on SkS during the past week:

El Niño Impacts

The international community must boost efforts to build the capacity for disaster risk management and readiness to prevent El Niño weather extremes from causing humanitarian crises in affected countries and impeding their development, the President of the United Nations Economic and Social Council (ECOSOC) said today.

“We must remember that El Niño is not a one-off event but recurring global phenomena that we must address for future generations and to achieve the Sustainable Development Goals (SDGs),” said ECOSOC President Oh Joon at the opening of a special meeting on Impacts of the 2015/16 El Niño phenomenon: Reducing risks and capturing opportunities at UN Headquarters in New York.

“All partners, the United Nations, international and regional organizations, civil society, the private sector and the scientific community, need to take coordinated and fortified action to tackle El Niño risks,” he added.

‘El Niño is not a one-off event,’ UN says, calling for action to address phenomenon’s impacts, UN News Center, May 6, 2016 

Toon of the Week

2016 Toon 19 

Hat tip to I Heart Climate Scientists



2016 SkS Weekly News Roundup #19

Posted on 7 May 2016 by John Hartz

A chronological listing of the news articles posted on the Skeptical Science Facebook page during the past week.

Sun May 1



COP21 LiveBlog

The Consensus Project Website



(free to republish)



The Scientific Guide to
Global Warming Skepticism

Smartphone Apps


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