Climate slowdown means extreme rates of warming 'not as likely'By Matt McGrath Environment correspondent, BBC NewsScientists say the recent downturn in the rate of global warming will lead to lower temperature rises in the short-term.Since 1998, there has been an unexplained "standstill" in the heating of the Earth's atmosphere.Writing in Nature Geoscience, the researchers say this will reduce predicted warming in the coming decades.But long-term, the expected temperature rises will not alter significantly. "The most extreme projections are looking less likely than before†-Dr Alexander Otto University of OxfordThe slowdown in the expected rate of global warming has been studied for several years now. Earlier this year, the UK Met Office lowered their five-year temperature forecast.But this new paper gives the clearest picture yet of how any slowdown is likely to affect temperatures in both the short-term and long-term.An international team of researchers looked at how the last decade would impact long-term, equilibrium climate sensitivity and the shorter term climate response.Transient natureClimate sensitivity looks to see what would happen if we doubled concentrations of CO2 in the atmosphere and let the Earth's oceans and ice sheets respond to it over several thousand years.Transient climate response is much shorter term calculation again based on a doubling of CO2.The Intergovernmental Panel on Climate Change reported in 2007 that the short-term temperature rise would most likely be 1-3C (1.8-5.4F).But in this new analysis, by only including the temperatures from the last decade, the projected range would be 0.9-2.0C."The hottest of the models in the medium-term, they are actually looking less likely or inconsistent with the data from the last decade alone," said Dr Alexander Otto from the University of Oxford."The most extreme projections are looking less likely than before."The authors calculate that over the coming decades global average temperatures will warm about 20% more slowly than expected.But when it comes to the longer term picture, the authors say their work is consistent with previous estimates. The IPCC said that climate sensitivity was in the range of 2.0-4.5C.Ocean storageThis latest research, including the decade of stalled temperature rises, produces a range of 0.9-5.0C."It is a bigger range of uncertainty," said Dr Otto."But it still includes the old range. We would all like climate sensitivity to be lower but it isn't."The researchers say the difference between the lower short-term estimate and the more consistent long-term picture can be explained by the fact that the heat from the last decade has been absorbed into and is being stored by the world's oceans.Not everyone agrees with this perspective.Prof Steven Sherwood, from the University of New South Wales, says the conclusion about the oceans needs to be taken with a grain of salt for now."There is other research out there pointing out that this storage may be part of a natural cycle that will eventually reverse, either due to El Nino or the so-called Atlantic Multidecadal Oscillation, and therefore may not imply what the authors are suggesting," he said.The authors say there are ongoing uncertainties surrounding the role of aerosols in the atmosphere and around the issue of clouds."We would expect a single decade to jump around a bit but the overall trend is independent of it, and people should be exactly as concerned as before about what climate change is doing," said Dr Otto.Is there any succour in these findings for climate sceptics who say the slowdown over the past 14 years means the global warming is not real?"None. No comfort whatsoever," he said.
Global warming has not stalled, insists world's best-known climate scientistJames Hansen: 'The deniers want the public to be confused.'Suggestions that global warming has stalled are a "diversionary tactic" from "deniers" who want the public to be confused over climate change, according to the world's best-known climate scientist. Prof James Hansen, who first alerted the world to climate change in 1988, said on Friday: "It is not true that the temperature has not changed in the two decades."Since 1998, when the Niño climate phenomenon caused global temperatures to soar, the rate of increase in warming has slowed, causing some sceptics to suggest climate change has stopped or that the effect of rising carbon dioxide levels on climate is not as great as previously thought.Prof Hansen, speaking to BBC Radio 4's Today programme, rejected both arguments. "In the last decade it has warmed only a tenth of a degree compared to two-tenths of a degree in the preceeding decade, but that's just natural variability. There is no reason to be surprised by that at all," he said. "If you look over a 30-40 year period the expected warming is two-tenths of a degree per decade, but that doesn't mean each decade is going to warm two-tenths of a degree: there is too much natural variability."Prof Hansen said the focus by some on "details" was a smokescreen. "This is a diversionary tactic. Our understanding of global warming and human-made climate change has not been affected at all," he said. "It's because the deniers [of the science] want the public to be confused. They raise these minor issues and then we forget about what the main story is. The main story is carbon dioxide is going up and it is going to produce a climate which is going to have dramatic changes if we don't begin to reduce our emissions." In 2008, scientists anticipated an upcoming slowing in temperature rises.Prof Hansen, who recently stepped down from his Nasa post after almost 50 years to focus on communication, said the forecast impact of climate change was little affected by the recent slowdown in the rate of rising temperatures."Climate is a complicated system but there is no change at all in our understanding of climate sensitivity [to carbon dioxide] and where the climate is headed," he said. "Our understanding of sensitivity is based on the Earth's history, not on climate models, and we have good data on how the Earth responded in the past when carbon dioxide changed. So there is no reason to change the forecast for the long term." On 9 May, a new study of lake sediments from a remote meteorite crater in Siberia showed temperatures in the region were 8C higher the last time CO2 levels were as high as they are today. Last week, atmospheric CO2 concentrations reached the milestone 400 parts per million, for the first time in millions of years.Prof Hansen has caused controversy in the past with statements including "CEOs of fossil fuel companies should be tried for high crimes against humanity and nature" and the assertion that "coal-fired power plants are factories of death".
Survey finds 97% of climate science papers agree warming is man-madeOverwhelming majority of peer-reviewed papers taking a position on global warming say humans are causing itOur team of citizen science volunteers at Skeptical Science has published a new survey in the journal Environmental Research Letters of over 12,000 peer-reviewed climate science papers, as the Guardian reports today. This is the most comprehensive survey of its kind, and the inspiration of this blog's name: Climate Consensus – the 97%.The surveyIn 2004, Naomi Oreskes performed a survey of 928 peer-reviewed climate papers published between 1993 and 2003, finding none that rejected the human cause of global warming. We decided that it was time to expand upon Oreskes' work by performing a keyword search of peer-reviewed scientific journal publications for the terms 'global warming' and 'global climate change' between the years 1991 and 2011.Our team agreed upon definitions of categories to put the papers in: explicit or implicit endorsement of human-caused global warming, no opinion, and implicit or explicit rejection or minimization of the human influence, and began the long process of rating over 12,000 abstracts.We decided from the start to take a conservative approach in our ratings. For example, a study which takes it for granted that global warming will continue for the foreseeable future could easily be put into the implicit endorsement category; there is no reason to expect global warming to continue indefinitely unless humans are causing it. However, unless an abstract included language about the cause of the warming, we categorized it as 'no opinion'.Each paper was rated by at least two people, and a dozen volunteers completed most of the 24,000 ratings. The volunteers were a very internationally diverse group. Team members' home countries included Australia, USA, Canada, UK, New Zealand, Germany, Finland, and Italy.We also decided that asking the scientists to rate their own papers would be the ideal way to check our results. Who knows what the papers say better than the authors who wrote them? We received responses from 1,200 scientists who rated a total of over 2,100 papers. Unlike our team's ratings that only considered the summary of each paper presented in the abstract, the scientists considered the entire paper in the self-ratings.The resultsBased on our abstract ratings, we found that just over 4,000 papers took a position on the cause of global warming, 97.1% of which endorsed human-caused global warming. In the scientist self-ratings, nearly 1,400 papers were rated as taking a position, 97.2% of which endorsed human-caused global warming. Many papers captured in our literature search simply investigated an issue related to climate change without taking a position on its cause.Our survey found that the consensus has grown slowly over time, and reached about 98% as of 2011. Our results are also consistent with several previous surveys finding a 97% consensus amongst climate experts on the human cause of global warming.The growth of the scientific consensus on human-caused global warming in the peer-reviewed literature from 1991 to 2011Why is this important?Several studies have shown that people who are aware of scientific consensus on human-caused global warming are more likely to support government action to curb greenhouse gas emissions. This was most recently shown by a paper just published in the journal Climatic Change. People will generally defer to the judgment of experts, and they trust climate scientists on the subject of global warming.However, vested interests have long realized this and engaged in a campaign to misinform the public about the scientific consensus. For example, a memo from communications strategist Frank Luntz leaked in 2002 advised Republicans, "Should the public come to believe that the scientific issues are settled, their views about global warming will change accordingly. Therefore, you need to continue to make the lack of scientific certainty a primary issue in the debate"This campaign has been successful. A 2012 poll from US Pew Research Center found less than half of Americans thought scientists agreed humans were causing global warming. The media has assisted in this public misconception, with most climate stories "balanced" with a "skeptic" perspective. However, this results in making the 2–3% seem like 50%. In trying to achieve "balance", the media has actually created a very unbalanced perception of reality. As a result, people believe scientists are still split about what's causing global warming, and therefore there is not nearly enough public support or motivation to solve the problem.Check our results for yourselfWe chose to submit our paper to Environmental Research Letters because it is a well-respected, high-impact journal, but also because it offers the option of making a paper open access, free for anyone to download.We have also set up a public ratings system at Skeptical Science where anybody can duplicate our survey. Read and rate as many abstracts as you like, and see what level of consensus you find. You can compare your results to our abstract ratings, and to the author self-ratings.Human-caused global warmingWe fully anticipate that climate contrarians will respond by saying "we don't dispute that humans cause some global warming." First, there are a lot of people who do dispute that humans cause any global warming. Our paper shows that their position is not supported in the scientific literature.Most papers don't quantify the human contribution to global warming, because it doesn't take tens of thousands of papers to establish that reality. However, as noted above, if a paper minimized the human contribution, we classified that as a 'rejection'. For example, if a paper were to say "the sun caused most of the global warming over the past century," that would be included in the less than 3% of papers rejecting or minimizing human-caused global warming.Many studies simply defer to the expert summary of climate science research put together by the Intergovernmental Panel on Climate Change (IPCC), which says that most of the global warming since the mid-20th century has been caused by humans. And according to recent research, that statement is actually too conservative. Of the papers which specifically examine the contributors to global warming, they virtually all conclude that humans are the dominant cause over the past 50 to 100 years.Summary of results from 8 studies of the causes of global warming.Most studies simply accept this fact and go on to examine the consequences of this human-caused global warming and associated climate change.Another important point is that once you accept that humans are causing global warming, you must also accept that global warming is still happening. We cause global warming by increasing the greenhouse effect, and our greenhouse gas emissions just keep accelerating. This ties in to the fact that as recent research has showed, global warming is accelerating. If you accept that humans are causing global warming, as over 97% of peer-reviewed scientific papers do, then this conclusion should not be at all controversial. Global warming cannot have suddenly stopped.Spread the wordGiven the importance of the scientific consensus on human-caused global warming in peoples' decisions whether to support action to reduce greenhouse gas emissions, and the public lack of awareness of the consensus, we need to make people aware of these results. To that end, design and advertising firm SJI Associates generously created a website pro-bono, centered around the results of our survey. The website can be viewed at TheConsensusProject.com, and it includes a page where consensus graphics can be shared via social media or email. Skeptical Science also has a new page of consensus graphics.Quite possibly the most important thing to communicate about climate change is that there is a 97% consensus amongst the scientific experts and scientific research that humans are causing global warming. Let's spread the word and close the consensus gap.
tl;dcWhat good will it do? Mother Earth will cleanse herself of all of the sinners, including me. We're on our way out anyway, so fuck it all.
Sidebar in today's newspaper: Oklahoma Tornadoes: Result of Global Warming?Ridiculous. There have been 3472 of the things since 1950 in Oklahoma. http://www.tornadohistoryproject.com/tornado/Oklahoma/map Change the view to 2500 per page and the entire state looks like tornado confetti. Global warming my butt. Kinfolks said Jed, move away from there.
Kind of like Jaws, Jaws II, III, IV, V, 27........ If you're being stalked by a deranged great white shark, or the deranged baby of the aforesaid deranged great white...for the next sequel, how bout' you move to oooohhhh....let's saaayyyy, North Dakota. The number of great white shark attacks in ND have dropped dramatically over the last 10 years there, Einstein.
They happen where cold and warm air meet. It's that simple. When the climate change topic came up on here a while back, I think I posted a link that said these types of events have actually slowed down lately - since we've been recording the events. The events have just gotten politicized by DC and sensationalized by the media. But I know I'm preaching to the choir here. There have been much more extreme changes in the climate centuries ago and long before factories and combustion engines came to being. It's cyclical.
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