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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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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?

 


2015 SkS Weekly Digest #31

Posted on 2 August 2015 by John Hartz

Contents: SkS Highlights, Improving the Weekly Digest, Toon of the Week, Quote of the Week, They Said What?: GOP Presidential Hopefuls, SkS in the News, SkS Spotlights: Asset Owners Disclosure Project, Poster of the Week, Coming Soon on SkS, and 97 Hours of Consensus: Dr. Pietr Sans

SkS Highlights

Conspiracy theories about Skeptical Science by John Cook drew the highest number of comments of the aarticles posted on SkS during the past week. Coming in second and thrid respectively were: 

Improving the Weekly Digest

The all-volunteer SkS author team is engaged in finding ways to improve the Wekly Digest in order to make it more attractive and useful to all of our readers. We would like your input and continuing particpation in this effort. In this context:

  • If you were responsible for producing the Weekly Digest, what changes would you make to its syle and content? 

Toon of the Week

 2015 Toon 31

Quote of the Week

Savio Carvalho of Amnesty International (AI), which is part of the UNMG, told IPS the post-2015 agenda has become an aspirational text sans clear independent mechanisms for people to hold governments to account for implementation and follow-up.

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2015 SkS Weekly News Roundup #31D

Posted on 2 August 2015 by John Hartz

Climate models are even more accurate than you thought

Global climate models aren’t given nearly enough credit for their accurate global temperature change projections. As the 2014 IPCC report showed, observed global surface temperature changes have been within the range of climate model simulations.

Now a new study shows that the models were even more accurate than previously thought. In previous evaluations like the one done by the IPCC, climate model simulations of global surface air temperature were compared to global surface temperature observational records like HadCRUT4. However, over the oceans, HadCRUT4 uses sea surface temperatures rather than air temperatures.

Climate models are even more accurate than you thought by Dana Nuccitelli, Climate Consensus-the 97%, The Guardian, July 31, 2015


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Indonesian translation of The Debunking Handbook

Posted on 1 August 2015 by BaerbelW

The Debunking Handbook is now available in Indonesian. Many thanks to Herendraswari Kusumawardani who did this 10th(!) translation of the handbook.

Note to other translators:

If you'd like to translate the Debunking Handbook into another language, please contact us (select "Enquiry about translations" from the drop-down list) to ensure nobody else is already working on your language. Then download this Word document which has all the English text in one column and a blank column in which to place the translated text. Once complete, send us back the document and we'll insert the translated text into the existing design. The already available translations can be found on this page.

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2015 SkS Weekly News Roundup #31C

Posted on 1 August 2015 by John Hartz

Climate pressures lead to rise in 'new-age orphans' in India's delta

Eleven-year old Srijita Bhangi sits in the waiting room of the jetty boat that connects her island home in Khulna to the mainland Sundarbans, near India's border with Bangladesh.

After spending a few days with her elderly grandparents - an effort to lift her most recent spell of depression - she is travelling back to the school hostel where she has lived since her parents left two years ago to find work in a garment factory 1,000 kilometres (620 miles) away, in Tamil Nadu.

Since then she has seen them only once, and the school lodging has effectively become her new home.

Climate pressures lead to rise in 'new-age orphans' in India's delta by Aditya Ghosh, Thomson Reuters Foundation, July 30, 2015


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Climate models are even more accurate than you thought

Posted on 31 July 2015 by dana1981

Global climate models aren’t given nearly enough credit for their accurate global temperature change projections. As the 2014 IPCC report showed, observed global surface temperature changes have been within the range of climate model simulations.

Now a new study shows that the models were even more accurate than previously thought. In previous evaluations like the one done by the IPCC, climate model simulations of global surface air temperature were compared to global surface temperature observational records like HadCRUT4. However, over the oceans, HadCRUT4 uses sea surface temperatures rather than air temperatures.

diagram

A depiction of how global temperatures calculated from models use air temperatures above the ocean surface (right frame), while observations are based on the water temperature in the top few metres (left frame). Created by Kevin Cowtan.

Thus looking at modeled air temperatures and HadCRUT4 observations isn’t quite an apples-to-apples comparison for the oceans. As it turns out, sea surface temperatures haven’t been warming fast as marine air temperatures, so this comparison introduces a bias that makes the observations look cooler than the model simulations. In reality, the comparisons weren’t quite correct. As lead author Kevin Cowtan told me,

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9 comments


10 Things We Learnt From Reddit About Understanding Climate Change

Posted on 30 July 2015 by Guest Author

This is a re-post from DeSmogBlog by Kyla Mandel

Two professors of cognitive psychology – Stephan Lewandowsky, from the University of Bristol, and Klaus Oberauer, from the University of Zurich – did a Reddit AMA (ask me anything) this week.

The topic up for discussion was: “The conflict between our brains and our globe: How will we meet the challenges of the 21st century despite our cognitive limitations?”

Climate change was (unsurprisingly) brought up repeatedly. Here are 10 things we learnt about understanding climate change:

1. Climate change is a BIG problem

Let’s face it: even the most optimistic among us can be overwhelmed by the sheer scale of what it means to tackle climate change. How can we push past this barrier?

I think [this is] a core problem about climate change: Even people who are willing to accept the scientific evidence are paralysed by the enormity of the task,” Lewandowsky said.

If you scare people without offering a solution then they manage their fear by denying the problem. So, the most important thing is to reinforce that there are solutions and that little steps do add up to something in the end. The situation is serious, yes, but in my view it is not hopeless.”

But what about the notion that yes, climate change exists, but we don’t need to worry because we’ll find ways to 'live with it'?

Unfortunately, it’s not that easy. There are certain aspects of climate change that will affect us all and “transcend boundaries,” Lewandowsky answered. This includes sea-level rise, extreme weather events such as flooding and drought, along with the spread of vector-borne diseases and mass migration.

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3 comments


2015 SkS Weekly News Roundup #31B

Posted on 29 July 2015 by John Hartz

2015 Arctic melting season won't break records, but could wipe the 'recovery'

Following the post of my colleague, Dana Nuccitelli on misreporting of ice trends, this article is a timely guest post by Neven Acropolis who runs the Arctic Sea Ice blog. - John Abraham

After the record smashing 2012 melting season had ended, Arctic sea ice watchers awaited the following melting season with a mix of anticipation and apprehension. Anticipation, because the annual ebb and flow of Arctic sea ice is one of the most spectacular natural events on the planet, accentuated by the dramatic loss of the past 30 years. Apprehension, because further losses would bring the Arctic yet one step closer to virtually ice-free conditions, an iconic image entailing many unpredictable consequences.

But just as the previous record low reached in 2007 was followed by a short-lived rebound, the 2013 melting season proved to be sufficiently cold and cloudy to make up for the large amount of thin first year ice in the Arctic. When the following 2014 melting season was relatively cold again, with little wind to compact the ice and transport it to lower latitudes, extent and area numbers yet again ended up well above 2012 levels. Consequently, this year’s melting seasonstarted out with more volume and more multi-year ice.

2015 Arctic melting season won't break records, but could wipe the 'recovery' by Neven Acropolis, Climate Consensus-the 97%, The Guardian, July 29, 2015


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2015 Arctic melting season won't break records, but could wipe the 'recovery'

Posted on 29 July 2015 by Neven

After the record smashing 2012 melting season had ended, Arctic sea ice watchers awaited the following melting season with a mix of anticipation and apprehension. Anticipation, because the annual ebb and flow of Arctic sea ice is one of the most spectacular natural events on the planet, accentuated by the dramatic loss of the past 30 years. Apprehension, because further losses would bring the Arctic yet one step closer to virtually ice-free conditions, an iconic image entailing many unpredictable consequences.

sea ice concentration

Arctic sea ice concentration on July 26, 2015. Source: University of Bremen.

But just as the previous record low reached in 2007 was followed by a short-lived rebound, the 2013 melting season proved to be sufficiently cold and cloudy to make up for the large amount of thin first year ice in the Arctic. When the following 2014 melting season was relatively cold again, with little wind to compact the ice and transport it to lower latitudes, extent and area numbers yet again ended up well above 2012 levels. Consequently, this year’s melting seasonstarted out with more volume and more multi-year ice.

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10 comments


2015 SkS Weekly News Roundup #31A

Posted on 28 July 2015 by John Hartz

40 percent of adults on Earth have never heard of climate change

A major concern for climate activists is figuring out what drives the public’s beliefs about climate change. This information can help scientists better engage with the public and help activists understand what factors are likely to make people take climate change seriously as a threat.

Until now, most research into public attitudes on climate change have focused on Western nations, like the United States, Europe and Australia, leaving scientists with little knowledge of how much awareness there is about climate change in other parts of the world and how people feel about it. But a new study, published Monday in the journal Nature Climate Change, provides a more inclusive look at the issue, giving scientists greater insight into what factors are most likely to make people care about climate change — if they know it’s happening at all.

The study focused on two major questions: what factors most influence whether a person is aware of climate change and, for those that know it’s happening, what factors influence how big of a risk that person thinks it poses. The researchers found that, worldwide, education is the biggest predictor of climate change awareness. Major factors that affected a person’s risk perception included understanding that climate change is caused by humans — this was especially true in the Americas and Europe — and noticing local changes in temperature, a particularly high indicator in many countries in Africa and Asia.

40 percent of adults on Earth have never heard of climate change by Chelsea Harvey, Energy & Environment, Washington Post, July 27, 2015


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The Daily Mail and Telegraph get it wrong on Arctic sea ice, again

Posted on 28 July 2015 by dana1981

Cherry-picking is one of the five telltale techniques of climate change denial. By focusing on short-term blips in noisy data, those who want to maintain the status quo can distract from the long-term threats posed by climate change. Climate contrarians most frequently deploy this strategy using global temperature and Arctic sea ice data.

A recent study in Nature Geoscience concluded that, not surprisingly, there is a strong relationship between the summer temperatures in the Arctic (specifically the number of “melting degree days”), and the amount of sea ice that melts in a given year. 2013 happened to be a relatively cool year in the Arctic – the coolest since 2004. As a result, there was relatively little ice melt in 2013. The annual minimum Arctic sea ice extent and volume were their largest since at least 2009, or perhaps as far back as 2005, according to the data used in this new study.

The following figure from the paper is as clear as ice – while there was a short-term increase from 2012 to 2013, the Arctic has lost more than half its sea ice over the past three decades.

sea ice volume

PIOMAS model Arctic sea ice volume for autumn 1980–2014 (solid line) and spring 1981–2014 (dashed line). CryoSat-2 volume estimates (red stars) are plotted for 2010–2014.

The following video by programmer Andy Lee Robinson also illustrates the dramatic rate of sea ice decline over the past 35 years.

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2015 SkS Weekly News Roundup #30D

Posted on 27 July 2015 by John Hartz

5 bold and beautiful solar projects from around the world

China is building its largest solar plant covering 6,301 acres in the Gobi desert and with capacity to provide electricity to 1 million households.

This is just another record breaker for China. But there’s good reason.

In a recent Greenpeace East Asia investigation, we found that air pollution levels have improved in the first six months of 2015, though still remain below global and domestic standards. Once completed the new solar plant will cut standard coal use by 4.26 million tons every year, reducing emissions of carbon dioxide and sulfur dioxide by 896,000 tons and 8,080 tons, respectively, according to state-run Xinhua news agency.

It’s part of a global trend. Check out these other bold and beautiful solar projects from around the world. Which one is your favorite?

5 Bold and Beautiful Solar Projects From Around the World by Shuk-Wah Chung, Greenpeace East Asia, EcoWatch, July 24, 2015


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Conspiracy theories about Skeptical Science

Posted on 27 July 2015 by John Cook

There is a growing body of research linking climate science denial and conspiratorial thinking. While Stephan Lewandowsky's Moon Landing paper has attracted most of the attention, another important paper from Yale University has flown somewhat under the radar. This research found that when those who deny climate change are asked to name the first thing that came to mind regarding climate change, the most common type of response involved conspiracy theories.

Smith_conspiracy.jpg

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20 comments


2015 SkS Weekly Digest #30

Posted on 26 July 2015 by John Hartz

SkS Highlights

The importance of good climate communication: a recent Arctic example by John Mason attracted the highest number of comments of the articles posted on SkS during the past week. Global warming deniers are an endangered species by Dana drew the second highest number of comments. 

Quote of the Week

Climate deniers who claim that thousands of scientists are engaging in a global fraud are "one step way from a conspiracy theory" that is too fantastical to be even feasible, he added.

"Think about it. We have an administration that could not roll out a proper health care website. You think they can manage a global scientific conspiracy? They could not do it if they wanted to," said Titley*, who also holds a doctorate in meteorology. And he scoffed at the idea that scientists are deliberately lying about climate change just to obtain short-term research grants.

*David Titley, Ret. Rear Adm., U.S Navy 

Navy climate change expert sees opponents ignoring science by Brian Nearing, Times Union (Albany, NY), July 22, 2015 

Toon of the Week

2015 Toon 30 

Hat tip to I Heart Climate Scientists 

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2015 SkS Weekly News Roundup #30C

Posted on 25 July 2015 by John Hartz

A new climate-change danger zone?

w much does the climate have to change for it to be “dangerous”? This question has vexed scientists ever since the first climate models were developed, back in the nineteen-seventies. It was provisionally answered in 2009, though by politicians rather than scientists. According to an agreement known as the Copenhagen Accord, which was brokered by President Barack Obama, to avoid danger, the world needs “to hold the increase in global temperature below 2 degrees Celsius” (3.6 degrees Fahrenheit).

Now a group of climate modellers is arguing that the danger point is, in fact, a lot lower than that. In a paper set to appear online this week in Atmospheric Chemistry and Physics, the modellers, led by James Hansen, the former director of NASA’s Goddard Institute for Space Studies, warn that an increase of two degrees Celsius could still be enough to melt large portions of Antarctica, which, in turn, could result in several metres’ worth of sea-level rise in a matter of decades. What’s important about the paper from a layperson’s perspective—besides the fate of the world’s major coastal cities, many of which would be swamped if the oceans rose that high—is that it shows just how far from resolved, scientifically speaking, the question of danger levels remains. And this has important political implications, though it seems doubtful that politicians will heed them.

A new climate-change danger zone? by Elizabeth Kolbert, The New Yorker, July 23, 2015


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Scientific consensus and arguments from authority

Posted on 24 July 2015 by Guest Author

This is a re-post of Potholer's latest YouTube video

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2015 SkS Weekly News Roundup #30B

Posted on 23 July 2015 by John Hartz

Climate treaty's finances on shaky ground

Faith in the Green Climate Fund, the finance arm long believed to hold a key to achieving a global climate change accord in Paris in December, is beginning to wane.

The Green Climate Fund is supposed to be the primary distributor of tens of billions of dollars in climate aid to help the world's poorest countries deal with climate change caused primarily by the actions of others. It was designed to help heal the deep divisions between rich and poor nations that have long dimmed hopes for a meaningful global warming solution. 

But with just one more board meeting to go before the Paris climate talks begin, the money it has to work with is not close to what's needed, the $3 billion contribution from the United States is looking iffy, and the fund has partnered with several financial institutions that developing nations distrust. 

Climate Treaty's Finances on Shaky Ground by Elizabeth Douglass, InsideClimate News, July 20, 2015


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The importance of good climate communication: a recent Arctic example

Posted on 23 July 2015 by John Mason

Here's the abstract of a new paper in Nature Geoscience on Arctic sea-ice volume:

Changes in Arctic sea ice volume affect regional heat and freshwater budgets and patterns of atmospheric circulation at lower latitudes. Despite a well-documented decline in summer Arctic sea ice extent by about 40% since the late 1970s, it has been difficult to quantify trends in sea ice volume because detailed thickness observations have been lacking. Here we present an assessment of the changes in Northern Hemisphere sea ice thickness and volume using five years of CryoSat-2 measurements. Between autumn 2010 and 2012, there was a 14% reduction in Arctic sea ice volume, in keeping with the long-term decline in extent. However, we observe 33% and 25% more ice in autumn 2013 and 2014, respectively, relative to the 2010–2012 seasonal mean, which offset earlier losses. This increase was caused by the retention of thick sea ice northwest of Greenland during 2013 which, in turn, was associated with a 5% drop in the number of days on which melting occurred—conditions more typical of the late 1990s. In contrast, springtime Arctic sea ice volume has remained stable. The sharp increase in sea ice volume after just one cool summer suggests that Arctic sea ice may be more resilient than has been previously considered.

OK, let's pick this apart. Arctic sea-ice volume is the trickiest of the sea-ice variables to measure. Extent and area are by contrast straightforward. Volume depends on the survival of multi-year ice in any melt season. A pronounced melt season, like 2012, sees some of the multi-year ice lost. But if any of the ice that didn't melt in 2012 makes it through the 2013 season, you are going to get a volume increase. The authors state that they observed 33% more ice volume in autumn 2013 relative to the 2010-2012 mean. They go on to state that in 2014 there was 25% more ice volume relative to 2010-2012 – in other words it dropped again. That shows up on the following ice thickness distribution plot: the thickest ice is in red. Big red blob for 2013, much smaller one for 2014.

ice thickness map

Such observations are reasonably consistent with PIOMAS:

arctic sea ice volume - PIOMAS

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Global warming deniers are an endangered species

Posted on 22 July 2015 by dana1981

At the end of this year there will be a critically important international climate change conference in Paris. At this conference, nations will attempt to reach an agreement to reduce greenhouse gas emissions and slow global warming.

Over the past few months there’s been a flood of big climate-related news, most of which will help build support and pressure for a strong agreement to curb global warming at the Paris conference. The political and social climate is shifting, and those in denial about human-caused climate change are struggling to adapt.

Scientific research underscores climate risks

John Abraham recently reported on two separate studies published in Nature andNature Climate Change, both of which found that global warming is intensifying several types of extreme weather. California is in the midst of a drought unprecedented in over a millennium, a heat wave is killing thousands of people in India and Pakistan, another has been baking Europe, and it seems as though half of North America is on fire.

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10 comments


2015 SkS Weekly News Roundup #30A

Posted on 21 July 2015 by John Hartz

4C degree rise in global temperature may make outdoor work impossible in North India

If the world warms up by 4 degrees Celsius, there is 30 per cent probability that temperatures will be so high that even moderate outdoor work cannot be carried out in the hottest month in northern India, a study on the risks of climate change has said.

There would also be a 40 per cent chance that individuals in northern India will not be able to participate in competitive outdoor activities in summertime if global average temperature rises on an average by one degree.

An international group of climate scientists, energy analysts and experts from finance and military recently released an independent assessment of the risks of climate change commissioned by the United Kingdom's Foreign and Commonwealth Office.

4 Degree Rise in Global Temperature May Make Outdoor Work Impossible in North India: Study, All India/KDTV. July 19, 2015


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NOAA State of the Climate report: Which seven records were broken in 2014?

Posted on 21 July 2015 by Guest Author

This is a re-post from Carbon Brief by Robert McSweeney

From greenhouse gas levels to ocean heat content, 2014 was a record-breaking year for the Earth system in many different ways. That's the finding of the latest State of the Climate report from the US National Oceanic and Atmospheric Administration's (NOAA) published today.

Now in its 25th year, the report provides a checkup of global climate using data collected from land, sea, ice and space. We take a look at seven of the records that tumbled last year.

Greenhouse gases

All the major greenhouse gases in the atmosphere, including carbon dioxide, methane and nitrous oxide, hit record high average concentrations last year.

After briefly passing 400ppm in May 2013, carbon dioxide levels at Mauna Loa in Hawaii stayed above this mark for the whole of April, May and June in 2014, the report says. Globally, 1.9ppm of carbon dioxide was added to the atmosphere in 2014, taking the average for the year to 397.2ppm.

State Of Climate 2014_Fig1

Global average carbon dioxide concentrations since 1980, with photo of Mauna Loa Observatory in background. Adapted from Figure 2.36 in State of the Climate in 2014

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