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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.
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?
The following article is reprinted by permission of its author, Stephen Leahy, who writes for the Inter Press Service (IPS) News Agency. To access the article as posted on the IPS website, click here.
COP19 delegates huddle to resolve the issue of loss and damage. Credit: Courtesy of ENB
WARSAW, Nov 24 2013 (IPS) -The U.N. climate talks in Warsaw ended in dramatic fashion Saturday evening in what looked like a schoolyard fight with a mob of dark-suited supporters packed around the weary combatants, Todd Stern of the United States and Sai Navoti of Fiji representing G77 nations.
It took two weeks and 36 straight hours of negotiations to get to this point.
At issue in this classic North versus South battle was the creation of a third pillar of a new climate treaty to be finalised in 2015. Countries of the South, with 80 percent of the world’s people, finally won, creating a loss and damage pillar to go with the mitigation (emissions reduction) and adaptation pillars.
Super-typhoon Haiyan’s impact on the Philippines just days before the 19th Conference of the Parties (COP19) amply illustrated the reality of loss and damages arising from climate change. Philippines lead negotiator Yeb Saño made an emotional speech announcing “fast for the climate” at the COP19 opening that garnered worldwide attention, including nearly a million YouTube views
Recently NASA reported that this year’s maximum wintertime extent of Antarctic sea ice was the largest on record, even greater than the previous year’s record.
This is understandably at odds with the public’s perception of how polar ice should respond to a warming climate, given the dramatic headlines of severe decline in Arctic summertime extent. But the “paradox of Antarctic sea ice” has been on climate scientists' minds for some time.
Continental v. sea ice
First off, sea ice is different to the “continental ice” associated with polar ice caps, glaciers, ice shelves and icebergs. Continental ice is formed by the gradual deposition, build up and compaction of snow, resulting in ice that is hundreds to thousands of metres thick, storing and releasing freshwater that influences global sea-level over thousands of years.
Sea ice, though equally important to the climate system, is completely different. It is the thin layer (typically 1-2m) of ice that forms on the surface of the ocean when the latter is sufficiently cooled enough by the atmosphere.
From there sea ice can move with the winds and currents, continuing to grow both by freezing and through collisions (between the floes that make up the ice cover). When the atmosphere, and/or ocean is suitably warm again, such as in spring or if the sea ice has moved sufficiently towards the equator, then the sea ice melts again.
As I study climate science, I draw pictures—my way of taking notes. At first, these illustrations were for myself, but with help from Skeptical Science authors, I've created many that are now in our climate graphics resources:
As with all our resources, these images are available to anyone to republish under our creative commons license. I will be adding to these, and when an image has a story of discovery behind it, I'll share it as a look behind the lines.
Behind the lines with Herschel's Discovery
A recent illustrated project is our interactive climate history timeline, based on a post by John Mason and converted into it's interactive format by Paul D., with editing by Paul and Baerbel. I created the icons and some of the illustrations that accompany various passages. One of the first (in time sequence) summarizes Herschel's discovery of infra-red:
Figure: Depiction of Herschel's discovery of infra-red light
Herschel's objective was to measure the temperature of the different wavelengths of light revealed by a prism. I had a mental image of the experiment from textbooks: Light source, prism, rainbow colors, and a very dignified Herschel. First decision: get rid of Herschel so I could finish the illustration within my deadline.
Second, confirm that I was placing the surviving elements, sun (light source), prism, light rays, in a defensible orientation:
I like to personally verify details in a drawing, when possible. I had no trouble finding a prism among my astro-junk (acquired from years of astronomy outreach), and used it to examine the relative position of the light scattering:
New research by Kevin Trenberth and John Fasullo of the National Center for Atmospheric Research investigates how the warming of the Earth's climate has behaved over the past 15 years compared with the previous few decades. They conclude that while the rate of increase of average global surface temperatures has slowed since 1998, melting of Arctic ice, rising sea levels, and warming oceans have continued apace.
The widespread mainstream media focus on the slowed global surface warming has led some climate scientists like Trenberth and Fasullo to investigate its causes and how much various factors have contributed to the so-called 'pause' or 'hiatus.' However, the authors note that while the increase in global temperatures has slowed, the oceans have taken up heat at a faster rate since the turn of the century. Over 90 percent of the overall extra heat goes into the oceans, with only about 2 percent heating the Earth's atmosphere. The myth of the 'pause' is based on ignoring 98 percent of global warming and focusing exclusively on the one bit that's slowed.
Nevertheless, the causes of the slowed global surface temperature increase present an interesting scientific question. In examining changes in the activity of the sun and volcanoes, Trenberth and Fasullo estimated that they can account for no more than a 20 percent reduction in the Earth's energy imbalance, which is what causes global warming. Thus the cause of the slowed surface warming must primarily lie elsewhere, and ocean cycles are the most likely culprit.
Trenberth and Fasullo found that after the massive El Niño event in 1998, the Pacific Ocean appears to have shifted into a new mode of operation. Since that time, Trenberth's research has shown that the deep oceans have absorbed more heat than at any other time in the past 50 years.
Arctic thaw tied to European, US heatwaves and downpours
Canada short on time for climate plan
Is Bjorn Lomborg right to say fossil fuels are what poor countries need?
Large companies prepared to pay price on carbon
Local climate predictions stay uncertain
Short-cut to produce hydrogen seen as step to cleaner fuel
Some good news (and plenty of bad) in NRC abrupt climate change report
Thanks for killing the planet, boomers!
The apocalypse is coming — and technology can’t save us
The (in)sanity of climate change
The Montreal Protocol, a little treaty that could
The other climate problem: CO2 threatens marine life
Arctic thaw tied to European, US heatwaves and downpours
A thaw of Arctic ice and snow is linked to worsening summer heatwaves and downpours thousands of miles south in Europe, the United States and other areas, underlying the scale of the threat posed by global warming, scientists said on Sunday.
Their report, which was dismissed as inconclusive by some other experts, warned of increasingly extreme weather across "much of North America and Eurasia where billions of people will be affected".
The study is part of a drive to work out how climate change affects the frequency of extreme weather, from droughts to floods. Governments want to know the trends to plan everything from water supplies to what crops to plant.
But the science of a warming Arctic is far from settled.
Climate Change: Years of Living Dangerously by Rob Painting is about the new television series on climate change being made by for the U.S. Showtime cable televison network. The series, produced by Hollywood heavyweights James Cameron and Jerry Weintrub, examines the impacts of climate change on people around the world. This posting, including video, garnered the most commebnts of the articles posted on SkS during the past week.
The Scientific Guide to Global Warming Skepticism has been translated into 18 languages. The latest translation is Swedish. Many thanks to Katarina Kaudern for her work translating the guide and to Emma Andersson and Ole Martin Christensen for proofreading it.
Note to other translators:
If you'd like to translate the Guide into another language, there are two documents to help you: a two-column Word document with all the English text in one column and a blank column to place the translated text, plus a PDF Overview of the Guide to clearly mark each section.
Please download the Word document and email the document back to us with the translated text. We'll then insert that into the existing design. But best first to contact me by selecting "Enquiry about translations" from the contact form's dropdown menu to ensure no one else is already working on your language. Note: the following languages have already been translated:
Warm Arctic waters emit carbon, though region is carbon sink overall
White House directs U.S. agencies to double renewable energy use
Why some meteorologists still deny global warming
ALEC calls for penalties on 'freerider' homeowners
An alliance of corporations and conservative activists is mobilising to penalise homeowners who install their own solar panels – casting them as "freeriders" – in a sweeping new offensive against renewable energy, the Guardian has learned.
Over the coming year, the American Legislative Exchange Council (Alec) will promote legislation with goals ranging from penalising individual homeowners and weakening state clean energy regulations, to blocking the Environmental Protection Agency, which is Barack Obama's main channel for climate action.
Details of Alec's strategy to block clean energy development at every stage – from the individual rooftop to the White House – are revealed as the group gathers for its policy summit in Washington this week.
Those claims appeared in mainstream newspapers during the lead-up to the invasion of Iraq in 2003. All those claims were false. The nonexistence of Weapons of Mass Destruction (WMDs) in Iraq immediately prior to the invasion and the absence of links between Iraq and al-Qaida eventually became the official U.S. position with the Duelfer Report and the report of the U.S. Senate Select Committee on Intelligence.
A decade later, those media failures are relevant not only because of the war's six-figure death toll and because the Iraqi per capita GDP has so far failed to return to prewar levels, but also because they remind us that the media, including highly reputable newspapers, can sometimes get things quite wrong.
James Cameron, the creator and director of many smash hit movies, has teamed up with producer Jerry Weintraub to make a television series on climate change for the Showtime television channel. The series, according to the promotional trailer below, seems to focus of the human story of climate change - how climate has already begun to impact the lives of people all around the world.
In the trailer, James Cameron says:
"Everybody thinks this is about melting glaciers and polar bears. I think it's a big mistake. This is one hundred per cent a people story"
I believe he's right. Even though Skeptical Science's core message is about the observational evidence underpinning the science of climate change, facts alone are unlikely to be enough to turn public opinion around. People remember human stories better than facts and figures, so examining the impacts of climate change on people around the world may leave a longer-lasting impression on viewers.
Sure, SkS regulars may take issue with the 99% analogy used by James Cameron, rather than the 97% which frequently appears in the scientific literature, including our study, Cook et al (2013). And with the claim by Weintraub that hurricanes are twice as bad as they ever were (they're not). Aside from these slight flaws it is encouraging to see one of the greatest filmakers of our time turn his talents toward communicating the urgency of combating climate change.
It looks like past IPCC predictions of sea level rise were too conservative; things are worse than we thought. That is the takeaway message from a new study out in Quaternary Science Reviews and from updates to the IPCC report itself. The new study, which is also discussed in depth on RealClimate, tries to determine what our sea levels will be in the future. What they found isn't pretty.
Predicting of sea level rise is a challenging business. While we have good information about what has happened in the past, we still have trouble looking into the future. So, what do we know? Well it is clear that sea levels began to rise about 100 years ago. This rise coincided with increasing global temperatures.
What causes sea level to rise? Really three things. First, water expands as it heats. Second, glaciers melt and water flows to the oceans. Third, the large ice caps on Greenland and Antarctica can melt and the liquid water enters the ocean; often the water transfer is added by calving at the ice fronts which result in icebergs that float into the ocean. In the past, much of the sea level rise was related to the first cause (thermal expansion). Now, however, more and more sea level rise is being caused by melting ice.
But this is all the past. What we really want to know is, how much will sea level rise in the future? There are a number of ways to predict the future. First, we can look at the deep past and see how sea level changed with Earth temperature long ago.
A second way to predict the future is through computational models. These models are computer programs which create a virtual-reality of the Earth. These virtual reality models are very useful because they allow scientists to play "what if" scenarios; but, they have their weaknesses as well. One of their weaknesses is that they don't necessarily capture all of the phenomena which cause sea level rise. It is believed by most scientists that the computer programs are too conservative.
How does this all relate to the current study? Well the authors took a different approach. They decided to ask the scientists themselves. What do they think sea level rise will be by 2100 and 2300 under different greenhouse gas scenarios? The authors found 360 sea-level experts through a literature survey. They then worked to find contact information for these scientists and finally, they sent a questionnaire. After receiving 90 expert judgments from 18 countries, the results were tallied. So, what do experts think?
Sea level rise over the period 2000–2100 for high and low warming scenarios. The ranges show the average numbers given across all the experts. For comparison we see the NOAA projections of December 2012 (dashed lines) and the new IPCC projections (bars on the right).
An update on risks of abrupt jolts from global warming
Bloomberg LP launches first tool that measures risk of 'unburnable carbon' assets
Climate change is not the future
Climate change: No longer electoral Kryptonite!
Climate change will pose rising burden on U.S. Taxpayer
Methane: It’s leaking out of the Arctic Ocean
No climate-change deniers to be found in the reinsurance business
Scientists warn that warming "will be hard to reverse"
Something in the weather tells us climate change is real
Temperature limit too high to avoid climate change
Al Gore is a vegan now — and we think we know why
And so it is actually quite remarkable that, as Forbes reported in this week’s issue and The Washington Post confirmed with a source close to Gore on Monday, he has gone vegan. Forbes merely tossed in a throwaway line referring to Gore as “newly vegan,” in a story about investors looking at ways of replacing eggs with plant-based formulas. The Post was unable to get any further details beyond confirmation from an unnamed Gore associate.
Thanks to the generosity of Skeptical Science contributors we are happy to report that Cowtan and Way (2013) is now open access and freely available to the public. We hope this will help to advance the discussion on coverage bias in the temperature record. We would like to thank everyone who has so generously contributed.
As a bonus, here is a poster which I took to the 2013 EarthTemp meeting at the DMI in Copenhagen last June. I was very fortunate to be able to attend this meeting, and talking to the experts there was critical to understanding the behaviour of air temperatures over sea ice - this led to section 5 in the paper and our more recent update.
Coverage of the paper has, predictably, ranged from the outstanding to the abominable. However some of the resulting conversations have already strengthened our results and are opening new lines of investiagation. My favourite quote is from William M. Connolley: "... anyone could have done it. Well, not quite, because they did it carefully". One of the things which still surprises me about our paper is that no one else beat us to it. And if it can be said of our work that "they did it carefully", then we have achieved one of our primary goals.
Several surveys have found relatively low acceptance of human-caused global warming amongst meteorologists. For example, a 2009 survey found that among Earth scientists, only economic geologists (47 percent) had lower acceptance of human-caused global warming than meteorologists (64 percent). A new paper by social scientists from George Mason University, the American Meteorological Society (AMS), and Yale University reports results from a survey of members of the AMS to determine the factors associated with their views on climate change.
Climate Scientists and Meteorologists, Apples and Oranges
The misrepresentations of the study have claimed that it contradicts the 97 percent expert consensus on human-caused global warming. The prior studies that have found this high level of consensus were based specifically on climate experts – namely asking what those who do climate science research think, or what their peer-reviewed papers say about the causes of global warming.
Posted on 30 November 2013 by Anne-Marie Blackburn
As discussed in a recent Skeptical Science post, John Cook responded to an article by Anthony Cox published in the Newcastle Herald. In his article, Cox attempts to cast doubt on the scientific consensus on man-made climate change by focusing on Cook et al.'s 2013 peer-reviewed paper. Cox effectively rejects the paper's findings by using a well-known technique developed in the 1970s by the tobacco industry: “unrealistic expectations”. More precisely, according to Cox a paper no longer supports the consensus if it does not explicitly specify the percentage of global warming caused by humans. As Cook points out, this allows Cox to ignore many papers that clearly state that human activities are behind ongoing climate change. For instance, a paper which includes
"Accumulating evidence points to an anthropogenic 'fingerprint' on the global climate change that has occurred in the last century"
does not endorse the scientific consensus when rated according to Cox's highly selective criterion. This can only make sense if people redefine rules to make it impossible to reach certain expectations, for whatever reasons. To the rest of us, it is clear that Cox is demanding an unreasonable level of scientific proof which simply cannot be met. No matter how much evidence supports anthropogenic climate change, it will be conveniently ignored since the bar has been set arbitrarily high without justification.
That those who reject the science of climate change use the same tactics as the tobacco industry is well documented. Yet some, including Cox, argue that the situations cannot be compared since the science supporting the link between tobacco and cancer/addiction is settled, unlike the science of man-made climate change. This ignores two things. First, the consensus on tobacco and its adverse effects on health was already strong when the tobacco lobby was trying to spread doubt about the science. There simply came a point when the evidence could no longer be ignored by the majority of people. Secondly, the consensus on man-made climate change emerged as a result of decades of research that have produced a large body of converging evidence. In other words, there is virtually no doubt that our climate is changing and that human activities are responsible for this change.
The tactics used by the tobacco industry were successful in delaying government regulation for years. Therefore it is not surprising to see these same techniques used by those who oppose action to reduce greenhouse gas emissions. Peter Sinclair has produced an excellent video that leaves no doubt about the similarities between what happened then and what is happening now. Some of the main parts are even played by the same people.
The end of 2013 is racing into view along with a cluster of holidays traditionally involving gifts. Many of us face the puzzling question of what will please or prove useful to people whom we care about. Gift selection is a problem easier to solve when thinking about children but increasingly difficult as our beneficiaries grow older and often more cranky.
Holidays and celebratory gatherings are also an opportunity to hone our diplomatic skills. When a large number of relatives gather under one roof we have an opportunity to practice biting our tongues in favor of peace and harmony. Friendship and familial ties should transcend our urge to reignite favorite arguments.
If embarrassing everybody with yet another argument is off limits, why not let gifts speak for you? If you find yourself grinding your teeth at other times of the year over disagreements about physics and how the subject pertains to the increasingly torrid surface of Earth, here is a selection of gifts as cathartic for you as they are improving for those very special people in your life, such as your lovable but crazy uncle who thinks the sea floor is littered with undetectable volcanoes.
For starters, give the free gift of bemused toleration. If somebody you care about dismisses overwhelming evidence and expert agreement telling us we've got a climate change problem thanks to our caveman enthusiasm for hydrocarbon combustion, let them be a "skeptic" for a day, even if strictly speaking the term "skeptic" has nothing to do with their proclivity.
The highly respected body of anonymous experts we call "they" say that laughter is the best medicine. Perhaps it's also true that laughter disarms and provides an opportunity for facts to slip into otherwise closed minds. Cartoonist Sidney Harris-- familiar from his work with the New Yorker, American Scientist and other publications-- has gathered his own and other cartoonists' work into a compendium, 101 Funny Things About Global Warming. Included is a special section built around quotes from famous people who should know better, such as Lee Ioccoca's "We've got to ask ourselves: how much clean air do we need?"
For history buffs in a state of divorce from the recorded timeline as it actually happened, Spencer Weart's revised and expanded The Discovery of Global Warming should be a stimulating read. Reknowned historian of science Weart takes us from ancient times to the present as better understanding emerges of seeming insignifcant humans being able to modify the planet on a huge scale.
The importance of public perception of scientific consensus has been established in a number of studies (e.g., here, here and here). Perhaps nothing underscores its importance more than the strenuous efforts that opponents of climate action have exerted in attacking consensus. For over two decades, fossil fuel interests and right-wing ideologues have sought to cast doubt on the consensus:
Attacks on any scientific consensus, whether it be human-caused global warming or the link between smoking and cancer, exhibit five characteristics of science denial. Similarly, the attacks against our paper have exhibited the same five characteristics. Some of these characteristics are on offer in an opinion piece by Anthony Cox published in the Newcastle Herald. I was granted the opportunity to publish a response in the Newcastle Herald, which was published today: