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Cornelius Breadbasket at 15:58 PM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
#6, doug_bostrom There may be another thread or article needed on this site to discuss extreme weather events this year - Southern France, Central Europe, Russia, China, Brazil, Tennessee, Pakistan and now Niger - and whether they should be linked to climate change. There is a very interesting response to these events from the Munich RE insurance company. They've undertaken research that demonstrates that since 1980 extreme weather events have tripled. The implication is that extreme weather events can no longer be dismissed as unrelated to climate change. Here is a link. -
huntjanin at 15:55 PM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
gpwayne: Thanks. FYI, I'm writing a book on sea level rise and, aside from the river-port-seaport idea, the only other positive benefit I'm come across is that maybe some former wetlands will be submerged and can thus return to their role as wetlands, rather than as, say, oil refineries. I don't know that you have to put this but it may be best to avoid making categorical statements unless you are 100% sure you are right. -
huntjanin at 15:50 PM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
In all respect, and meaning no offense, some of the comments above strengthen my belief, stated in this blog not long ago, that it is mistake to reduce complicated, multifaceted isses to simplistic explanations. These will give the deniers no end of free ammunition. In my opinion, the climate change believers must set their sights high, not low.Response: It is possible to accurately explain complicated science in simple terms. It's not easy, in fact, it's very difficult (a quick scan of the in-depth discussion on the Authors Forum shows that). But if we want the general public to understand what's happening to the climate, it's an effort worth trying. -
Doug Bostrom at 15:46 PM on 17 August 2010Of satellites and temperatures
Marcus, good point. I believe one of the problems here is, the message is not pleasing so indeed there's no being pleased by it. One alternative is to make up a story about a better message. Meta-comment, over and out. -
gpwayne at 15:45 PM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
huntjanin: "I can't believe that there will be absolutely NO benefits [to sea level rise]" Fair enough, but I couldn't find anything in the literature, in what was admittedly a short search. If you can find anything from a reasonably credible source I'll be glad to add it in. -
gpwayne at 15:43 PM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
A decision was taken to start a new thread with each 'basic' rebuttal, so I'm going to address a point or two made by Thingadonta:Some places, like the Himalayas and Greenland, with warmer temperatues will experience increased meltwater flows, because more areas are above 0 degrees celsius, which means more water, not less.
I assume you refer to air temperature. This is not what is causing the majority of melting of the Greenland ice cap - it is subduction of warmer sea water, melting of undersea buttresses that hold the glaciers in place, and some surface water that trickles down through fissures in the ice called moraines.This is also enhanced by more frequent floods.
Two things. Glaciers are shrinking. If glacier mass balance is consistently negative (80% display mass loss according to the WGMS) then the amount of spring melt water is going to be reduced, so less is available downsteam at lower altitudes. Secondly, more frequent floods are a liability, not an enhancement. The timing is crucial - flash floods that arrive after crops are planted simply wash the crops away. This is not very helpful, nor it is predictable.The list above is too one-sided to be taken seriously.
You'd need to provide the other side then, for your assertion to be taken seriously. Substantiate your claim please with facts. -
huntjanin at 15:41 PM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
I can't believe that there will be absolutely NO benefits, anywhere in the world, as a result of sea level rise. Might not some river ports become seaports?Response: Now that's thinking outside the box :-) -
Glenn Tamblyn at 15:39 PM on 17 August 2010Of satellites and temperatures
Here is a link to a previous post John has done on Satellites and Temperature http://www.skepticalscience.com/satellite-measurements-warming-troposphere.htm And if you want way too much information then follow John's link to this by Scott Church http://www.scottchurchdirect.com/docs/MSU-Troposphere-Review01.pdf In particular, his review of the work by Quiang Fu and others, looking at compensating for the fact that the T2 MSU's, that are used to read the lower & mid Troposphere temp's are affected by the fact that 15-20% of the signal is actually coming from the lower stratosphere. As a consequence of the fact that the stratosphere has cooled more than the troposphere has warmed, the satellite data products from both RSS & UAH are probably under reporting the actual temperature of the troposphere due to 'contamination' of the signal by cooling of the stratosphere. Church's review is thorough but long - 137 pages. But definitely worth reading. -
Marcus at 14:04 PM on 17 August 2010Of satellites and temperatures
The important point here, though, is how the Denialists keep changing the goal-posts every time the evidence doesn't suit their denial. When they thought the UAH data supported their claims of a cooling trend, they were all "well the Satellite record is so much more reliable than surface temperature readings". Now that the UAH is showing a definitive warming trend, now the Denialists are telling us that satellites are rubbish too. Seriously, there's no pleasing these people. What matters is the close correlation between surface & satellite based temperature measurements from at least *four* different sources! I mean, how much more EVIDENCE do these denialists need? -
Doug Bostrom at 13:37 PM on 17 August 2010Hockey stick is broken
McShane and Wyner is apparently yet another smoking "gub," looks like. Nailed by their lack of expertise? The tasty nugget at the center of the paper, for skeptics: In other words, our model performs better when using highly autocorrelated noise rather than proxies to predict temperature. The real proxies are less predictive than our "fake" data. It appears M&W compared the performance of proxies sensitive to regional changes against the global NH temperature record. Naturally, the thermometer on your porch (for instance) will turn out to be a poor proxy for global NH temperature if you're trying to tease out changes on the order of a couple of degrees. Even I should have been able to see that. Rats. Noted in various places. -
barry1487 at 13:27 PM on 17 August 2010Did global warming stop in 1998? (basic version)
It doesn't matter that they don't understand the quote. Jones' comment is an 'admission'. The rest of his work is 'fraudulent'. Agreeable propaganda is to an ideologue what a toy is to a child. -
muoncounter at 12:40 PM on 17 August 2010NASA-GISS: July 2010-- What global warming looks like
Nice new article, again in the Guardian: "Will this summer of extremes be a wake-up call?" Looking only at individual extreme events will not reveal their cause, just like watching a few scenes from a movie does not reveal the plot. But, viewed in a broader context, and using the logic of physics, important parts of the plot can be understood. ... We must face the facts: our emissions of greenhouse gases probably are at least partly to blame for this summer of extremes. Clinging to the hope that it is all chance, and all natural, seems naive. That sounds like it was actually written by (gasp) a scientist. Guess what: "Stefan Rahmstorf is Professor of physics of the oceans at Potsdam University, and a member of the German Advisory Council on Global Change." -
sailrick at 12:36 PM on 17 August 2010Hockey stick is broken
Regarding the supposed debunking of the hockey stick by McShane and Wyner, "A new Hockey Stick: McShane and Wyner August 16, 2010, by Tim Lambert http://scienceblogs.com/deltoid/2010/08/a_new_hockey_stick_mcshane_and.php -
John Brookes at 12:16 PM on 17 August 20102nd law of thermodynamics contradicts greenhouse theory
Fascinating to see Roy Spencer getting annoyed at denialists who won't allow radiation from the atmosphere to warm the surface of the earth. Click... -
CBW at 11:09 AM on 17 August 2010Did global warming stop in 1998? (basic version)
It's funny how the skeptics attacked Phil Jones credibility relentlessly, and still make snide references to "climategate," but they're only too happy to cite him as an expert over and over again for this one quote. It's just another bit of evidence that even they don't believe most of what they're saying. -
Bern at 10:52 AM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
That's a good suggestion, chriscanaris. Perhaps the discussion over the science should be redirected to the actual argument page, rather than this update post. It would be better placed there, in any event. -
chris1204 at 10:39 AM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
Doug, we could argue until the cows come home whether the Pakistani tragic floods are a product of climate change - basically we don't know. However, Thingadonta's right insofar as flood plains (not the situation in Pakistan which is monsoonal flooding) are good for agriculture - that's why they attracted human settlement in the first place. Could I suggest that we don't subvert John's Plain English project by arguments about the science climate change. As I understand it, all John's trying to do is to 'translate' existing pages into a more accessible format. Inevitably, some of us will disagree with some of the content - some of us may disagree with most of the content. However, we should reserve discussions of the content for the appropriate forum, eg, when a post is made specifically about some new aspect of the science or an old thread is revisited with new data. -
Doug Bostrom at 10:23 AM on 17 August 2010Did global warming stop in 1998? (basic version)
Paul, how about just a graph?
(from GISS Surface Temperature Analysis )
Lots of places there where we could bridge two data points with a plateau, a steep decline, a steep rise, whatever we want as long as the big picture is no concern.
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Doug Bostrom at 10:06 AM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
Whistling past the graveyard on adjustments spawned by flooding? What happens when a flood vastly exceeds ordinary cycles: Floods Could Have Lasting Impact for Pakistan KARACHI, Pakistan — Even as the government and international relief workers struggle to get food and clean water to millions of Pakistanis devastated by floods, concerns are growing about the enduring toll of the disaster on the nation’s overall economy, food supply and political stability. More rains battered the country Monday, adding to the worst flooding in memory and confronting Pakistan with a complex array of challenges, government and relief officials warned. Though they ranged over the immediate, medium and long term, nearly all needed to be addressed urgently for Pakistan to avoid lasting calamity. Providing clean water for millions and avoiding the spread of diseases like cholera was the first priority. But there were also looming food shortages and price spikes, even in cities, and the danger that farmers would miss the fall planting season, raising the prospect of a new cycle of shortfalls next year in a country that produces much of its own food. “There was a first wave of deaths caused by the floods themselves,” Maurizio Giuliano, a United Nations spokesman, said. “But if we don’t act soon enough there will be a second wave of deaths caused by a combination of lack of clean water, food shortages and water-borne and vector-borne diseases. The picture is a gruesome one.” The prospect of immediate hunger combining with long-term disruptions to the food cycle was a chief concern. The situation confronting Maqbool Anjum, 50, a small-scale wheat farmer in Khanpur district, in Southern Punjab, was typical. For the time being, he said in an interview by telephone: “We don’t have food rations in our house. There isn’t a single grain of flour with us right now.” For the last three weeks, he said, he and his family have survived on bread and vinegared pickles. There was no dry wood to light a fire in the stove. “What we’re doing is breaking off legs from our wooden bed and using that.” No one from the government or any relief organization had contacted them. Still, in less than two months, he and his brothers were supposed to re-seed the soil on about eight acres they own for next year’s wheat harvest. That may be impossible now. His seeds are lost, as was the cotton crop on part of that land, along with any income it may have brought. Two of his brothers’ homes were destroyed. For the time being he would try to survive on his wife’s salary of $50 a month as a health worker. But the prospect of mounting debt seemed inevitable. “It’ll take 3 to 4 years before we can grow anything on our land again,” so ruined was it, he said. Of the 4,000 people in his village, half of them also own agricultural land and were similarly wiped out. “Everything’s gone,” he said. “This is the worst rainfall my village has ever seen.” His struggle is multiplied by many millions across the country. The floods have submerged about 17 million acres of Pakistan’s most fertile croplands, in a nation where farming is an economic mainstay. The waters also killed more than 200,000 livestock, and washed away massive quantities of stored commodities that feed millions throughout the year. Relief workers warned that if farmers like Mr. Anjum missed the deadline to re-seed in the fall planting season, the nation could face the prospect of long-term shortages. More What was that about "beneficial to agriculture?" Pakistan has a fundamentalist insurgency bent on overthrowing the weak government. The insurgency is making public relations hay out of this situation. The government could well fall due to knock-on effects of the flood. The government has nuclear weapons which will change hands if that happens. Good situation? -
Climature at 10:03 AM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
Thingadonta: New to the blog and I do enjoy reading all of your comments but I have to say something about your comment about ancient Egypt. Though it is true that the seasonal floods were beneficial to the Egyptians, this was not the case for quite some time in paleolithic Egypt. In fact the Nile valley in Paleolithic Egypt flooded too much to sustain habitation. The Eqyptians didn't get to the Nile until around 7000 B.C.E. and only then it was seasonal. Just a clarification -
Paul Bell at 09:59 AM on 17 August 2010Did global warming stop in 1998? (basic version)
Phil Jones would disagree. From BBC interview: Q:Do you agree that from 1995 to the present there has been no statistically-significant global warming A: Yes http://news.bbc.co.uk/2/hi/science/nature/8511670.stmResponse: To understand the context of both this loaded question and Phil Jone's answer, you need to read Phil Jones' words and understand the nature of the statistics discussed. The issue is also discussed in more detail in this blog post by Alden Griffiths which was adapted from his video addressing the argument: 'Global warming has stopped'. -
CoalGeologist at 09:38 AM on 17 August 2010Plain English climate science - now live at Skeptical Science
This is an immensely valuable approach to the debate over human attribution of contemporary climate change (which, when everything is stripped away, is what all the controversy is about), but to me there's an important aspect missing, which is identifying the logical fallacies that commonly appear in skeptical arguments against AGW. There are some skeptical arguments that have scientific merit, for which there may be a variety of [apparently] contradictory evidence. In such cases, addressing the argument will come down to a question of listing and weighing the evidence, particularly in regards to its reliability. In many more cases, however, skeptical arguments against AGW entail invoking logical fallacies. Particularly common fallacies are: a) strawman arguments (intentionally or unintentionally misrepresenting the opposing view, for the express purpose of “disproving” it), b) red herring arguments (raising issues or evidence that are not relevant to the actual issue being debated), c) cherry picking (misrepresenting the weight of scientific evidence by focusing on evidence that supports a particular conclusion), d) ad hominem arguments (attacking the person who makes the argument, rather than the argument itself). e) etc. For example, the discussion about Did Global Warming Stop in 1998 makes reference to "cherry picking". And the discussion about The Rate of Melting of the Greenland Ice Sheet addresses what is essentially a "Red Herring" argument by Willis Eschenbach. (In other words, even if Eschenbach is correct, his argument is irrelevant!) These sorts of fallacies tend to occur again and again (and again!); only the specific details vary. True skeptics (i.e. those who are equally skeptical toward the arguments both for and against AGW) would benefit from learning how to identify these "type"-fallacies, as it will be easier for them to recognize similar sorts of fallacies in other circumstances. With regard to making the presentation easily accessible, which is the goal of this approach, one option would be to include an icon of a "red herring" or a "straw man" or a clump of cherries on the "Basic" response (or a picture of Al Gore for the "ad hominem" category ;-), which would link to a more detailed explanation of why the argument is fallacious on the "Intermediate" page. One potential argument against this approach would be that it presupposes a motive or intent in making a particular fallacious argument. While this may be true, my feeling is that "cherry picking is cherry picking", whether it is intentional or inadvertent. Our goal in science is an unbiased assessment of the evidence, and if a particular argument fails to adhere to this principle, the problem should be identified, irrespective of whether it was intentional or not. Just a suggestion! Thanks, as ever, for your efforts to shine a light on the scientific evidence relating to climate change! -
CoalGeologist at 09:34 AM on 17 August 2010Greenland has only lost a tiny fraction of its ice mass
This discussion provides an example of a "Red Herring" argument. Even if Eschenbach is factually correct regarding the projected date when the last remaining gram of ice in Greenland will melt, his argument has no relevance to understanding the magnitude of current climate change, its likely cause, and its likely impact on natural ecosystems and human civilization. Red herring arguments are frequent in AGW skepticism. BP.... I think it fair to say we are all in the process of learning some science. While we are engaged in this endeavor, I think communication is helpful, if not essential. You were correct, however, to point out that, aside from the "Butterfly Effect", climate change on Earth is unlikely to have any effect beyond the limits of our atmosphere. -
thingadonta at 09:29 AM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
The discussion above is very one-sided. It is well known that warmer climates in the last few thousand years generally have net benefits, not negatives. Of course the question depends on relative degree of warming, probably a little warming is good, too much not so good. One example from above. "glaciers...fresh water supplied each year by natural spring melt and regrowth cycles and those water supplies – drinking water, agriculture – may fail". This is only true in some areas. Some places, like the Himalayasand Greenland, with warmer temperatues will experience increased meltwater flows, because more areas are above 0 degrees celsius, which means more water, not less. This is also enhanced by more frequent floods. Floods are generally benfifical for argiculture. (That is why eg ancient Egypt was founded on the Nile). Every time there is a flood on the east coast of Australia farmers receive a net benefit. The media only reports on urban areas inundated (which amounts to <10% of such areas), but for example cyclones have been shown to greatly increase agricultural output in Queensland in months/years following a cyclonic depression. (Although they may negatively impact existing crops). The list above is too one-sided to be taken seriously. -
Doug Bostrom at 09:15 AM on 17 August 2010NASA-GISS: July 2010-- What global warming looks like
Perfect example of how researchers see their information completely mangled as it passes through the newsgrinder, only to have the blame thrown back in the wrong place (those darned alarmist scientists!): "There was a piece in the Telegraph, “Pakistan Floods: Climate change experts say global warming could be the cause.” The body of the story says, “Experts from the United Nations (UN) and universities around the world said the recent ‘extreme weather events’ prove global warming is already happening.” They didn’t say that, actually, the reporter did. The experts in the story actually were pretty clear that no weather event can be said to be caused by climate change, but rather that events like those we have witnessed are consistent with predicted changes." (emphasis mine) From the Knight Science Journalism Tracker, a fun site for keeping up w/science journalism including the "what" of science stories as well as the "how." -
dab57 at 09:08 AM on 17 August 2010The Good, The Bad and The Ugly Effects of Climate Change
Dear Skeptical Science; This is to thank you for your website. It is making very important contributions. I am the director of Collaborative Program on the Ethical Dimensions of Climate Change at Penn State University and a successful blog that covers climate change policy issues through an ethical prism. It is ClimateEthics.org. You might be interested to have a look. In any event, thanks for your website. Donald A. Brown, Associate Professor, Environmental Ethics, Science, and Law, Penn State. -
Doug Bostrom at 08:27 AM on 17 August 2010Of satellites and temperatures
Those wishing to avoid encouraging such projects as "theclimatescam.se" may wish to retrieve Paltridge 2009 from a less bizarre source. Here's a copy from a place w/no homepage at all: Trends in middle- and upper-level tropospheric humidity from NCEP reanalysis data Really, Peter, the company you keep. Tsk-tsk. As to the humidity trend, what's with the "if?" If you don't know whether humidity trends are taken into account when deriving temperature, why not find out? Christy & Spencer seem to place a high degree of confidence in deep atmosphere soundings: Assessment of precision in temperatures from the microwave sounding units Derivations do take humidity into account and appear to be tested against radiosonde measurements, as described by Christy and Spencer: Error Estimates of Version 5.0 of MSU–AMSU Bulk Atmospheric Temperatures -
Berényi Péter at 07:51 AM on 17 August 2010Greenland has only lost a tiny fraction of its ice mass
#1 Alan at 05:41 AM on 17 August, 2010 The relationship of the planet Earth to other constellations and local planetary bodies could be affected by this loss of ice [...] This is an area of research that needs to be probed further. No, it is not. Either learn some science or keep quiet, please. -
Berényi Péter at 06:50 AM on 17 August 2010Of satellites and temperatures
#21 doug_bostrom at 01:50 AM on 17 August, 2010 If there's a substantial issue it would be an error producing a trend artifact. Is there? If there is one, it should be a secular downward trend in upper tropospheric humidity. Paltridge 2009 is still looming above. He has used NCEP balloon radiosonde reanalysis data on face value and found considerable drying of upper troposphere. Of course there are known problems with radiosonde humidity measurements, but have a look at this graph (mid frame from Fig. 3 of the paper):
At 700 hPa (about 3000 m) temperature in the tropics is still well above freezing, so frost-related problems of humidity measurements can not possibly occur. I think this downward trend is particularly hard to be explained away.
If models used to convert brightness values in narrow microwave channels to proper temperatures do not take this trend into account, they can misidentify increased brightness due to increasing transparency of upper troposphere (making lower, warmer layers "visible" to satellites) to increasing temperature.
Theor Appl Climatol
DOI 10.1007/s00704-009-0117-x
Trends in middle- and upper-level tropospheric humidity from NCEP reanalysis data
Garth Paltridge, Albert Arking & Michael Pook
Received: 21 July 2008
Accepted: 4 February 2009
Published online: 26 February 2009
But not even average specific humidity has to decrease to fool model calculations. It is quite enough for horizontal humidity distribution to become a bit more uneven to increase average brightness. I do not know if we have ready-made data on trends in higher moments of humidity distribution, but it would worth the effort to have a peek.
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JHartman at 06:28 AM on 17 August 2010Plain English climate science - now live at Skeptical Science
Great basic explanation for the 1998 argument. I would suggest adding something to the end of the first paragraph: "What's more, globally, the hottest 12-month period ever recorded was from June 2009 to May 2010, as of June 2010." Or something to that effect, otherwise the information will be (unfortunately) quickly out of date. -
Alan2890 at 05:41 AM on 17 August 2010Greenland has only lost a tiny fraction of its ice mass
Further thoughts on Isostatic Rebound and the effects that will have on the planet Earths Greenland Ice mass. The removal of ice will see a 7.2 Mtr rise in sea levels. However, this simply relates to the mass of ice melting and causing this rise in sea levels. This does not take into account the displacement of water due to the rise in the Greenland land mass as that mass rises so will its continental shelves thus causing further water displacement. Again this ice loss does not address the return of the mantle to areas where the tectonic activity has caused the land to uplift As the mantle is a loosely defined mass the mantle movement will lead to a shift of mantle material to the Greenland land mass area. This will have an oblivious cause and effect on all the continental plates and their relationship to each other. Whilst on this subject of Isostatic Rebound. The relationship of the planet Earth to other constellations and local planetary bodies could be affected by this loss of ice not only in Greenland but in other places that have large ice sheets. The distribution of ice has contributed to the Earths relative stability in the general Cosmos by way of its equilibrium and declination. However, with the changes to the Earths land and sea masses it could be envisioned that the Earths equilibrium would be disturbed. This is an area of research that needs to be probed further. -
Phil at 05:33 AM on 17 August 2010Newcomers, Start Here
John, Could I suggest a small change to this sentence in the main post ? Climate skeptics vigorously attack any evidence for man-made global warming yet eagerly embrace any argument, op-ed, blog or study that refutes global warming. I think you should replace "eagerly" with "uncritically"; to me this then sums up the contrarian/denier (call it what you will) position very well and puts emphasis on the double standards that distinguish this position from proper scientific skepticismResponse: Good call, your wording expresses what I was thinking better than how I expressed it. Have updated the post and the short introductory paragraph on the homepage. Thanks for the feedback! -
NickD at 05:25 AM on 17 August 2010Plain English climate science - now live at Skeptical Science
Here is a discussion on the M & W (as of yet unpublished) paper. I'm sure RC will do a post after the paper has passed through review and is properly analyzed. For now it's much ado about nothing until it is published. Frankly I think the hockey stick thing has been beaten to death.Moderator Response: Further discussion of this would best be conducted at Is the hockey stick broken. -
Paul D at 04:34 AM on 17 August 2010Plain English climate science - now live at Skeptical Science
Re: McShane and Wyner... One of the issues in one of the CRU reports suggested statisticians and climate scientists should be working together more. Seems like they still aren't. Given the importance of the subject, I often find it scary how little money is actually spent on it. Yet on the one hand many skeptics want less spent! Can't remember where I read it but one professor and his students had to pay for their own air fare to get to a research expedition in the Arctic. He also said that their was hardly any temperature data for the seas around the Petermann glacier. Obviously there isn't great profits to be made out of this research! -
muoncounter at 04:30 AM on 17 August 2010NASA-GISS: July 2010-- What global warming looks like
#95: Extended quibbling over inconsequential errors in summaries seems like a pointless distraction when the simple statistics are so surprising. That sounds like a good motto; perhaps John should put it across the top of every page! Or email it to WattsAndCo. -
Doug Bostrom at 03:59 AM on 17 August 2010Hockey stick is broken
In another thread the so-far unpublished McShane and Wyner paper was pointed out by David Walters. Some (me, for instance) have speculated that McShane and Walters drop some remarks indicating their unfamiliarity with the topic of their statistical analysis, even as they suggest climate researchers in turn are suffering from a lack of statistical expertise. Perhaps this is in fact a problem? 1) Why did McShane and Wyner regress their proxy PCs against the global mean temperature time series rather than against the whole NH temperature field over time, like Mann does? In other words, why throw away all that detailed info and calibrate against aggregated data only? 2) Why did M&W not notice that their calibration using the first PC of the instrumental field, rather than the global mean of instrumental, gives a reconstruction indistinguishable from Mann et al. 2008? 3) …and why did they not use this calibration — also aggregated but apparently better — in their Bayesian run, when it also clearly gives the best fit even by their crippled (because again, taken relative to the instru mean time series, not the whole field) RMSE criterion? "Gavin's Pussycat" at OpenMind Ordinarily I don't think I'd be referring to a blog comment by a cat as opposed to a formal comment or the like but apparently this paper has been pushed into the limelight before benefiting from full review. So, fair game, I guess. -
davidwwalters at 03:34 AM on 17 August 2010Plain English climate science - now live at Skeptical Science
Thanx doug.....Like i said, i'm a lay person, but your take corresponded with my view of it. I just want to know so i can answer the deniers. I'll read more on "Is the hockey stick broken" -
Doug Bostrom at 03:23 AM on 17 August 2010Plain English climate science - now live at Skeptical Science
What struck me about McShane and Wyner's paper (besides the fact it's apparently not yet published) is the heavy load of extraneous material it carries outside of their core thesis, a well-developed perspective from the political viewpoint of the importance of their work. As well, they're working outside of their realm of expertise, as indicated by their remarks about the mysterious nature of natural variability for which they cite no references. I was struck by that because they mention their vaguely expressed worry in close proximity to their gentle chiding of climate researchers for not engaging with statisticians. Ironic. The "Hocky Stick" is discussed at SkS here: Is the hockey stick broken -
davidwwalters at 03:04 AM on 17 August 2010Plain English climate science - now live at Skeptical Science
I'm new here and i read another debunking claim of Mann's Hockey Stick by another statistician, by McShane and Wyner. They claim the proxy data is no good in reconstructing past temperatures. However i noticed where there is empirical data on temps, it seems to correlate to what the proxy generated models show. Anything you can say about McShane and Wyner's paper? http://www.e-publications.org/ims/submission/index.php/AOAS/user/submissionFile/6695?confirm=63ebfddf -
tobyjoyce at 02:14 AM on 17 August 2010Newcomers, Start Here
dhogaza #27, Slightly OT, but I cannot resist mentioning the Russian experiments with the Siberian Silver Fox. http://www.youtube.com/watch?v=PRQbSdMXBk0 This animal is a pretty savage canine, but breeders noted that in every litter there was sometimes one pup gentler and less aggressive that the rest. The experimenters started (in 1959) selecting and breeding the gentler animals and after about 50 generations, they had an animal capable of domestication. This was part of a documentary, which includes the suggestion that humans and dogs co-evolved - in other words, dogs' ability to track, hunt, and guard may have been much more valuable to our ancestors than to us. Where would we be without them? -
Models are unreliable
Pete Ridley - I believe that those various analyses you list are based on the GHCN database, which as I had noted has had a lot of analysis applied to it. The independent GSOD and satellite data sets match trends with the GHCN database (in pretty much any analysis whatsoever). This is shown in the Assessing global surface temperature reconstructions thread. That's an excellent support for the data, and indicates (in the absence of any contradictory data) that these trends are real. The lowest estimate on warming is from the UAH analysis of satellite data (~0.13 C/decade?), which has had some known issues. Averaging the various estimates of land/sea increase gives a number closer to ~0.16 C/decade. -
Doug Bostrom at 02:02 AM on 17 August 2010NASA-GISS: July 2010-- What global warming looks like
Thinking of this in comparison w/how the analysis at WUWT of snowfall records ignored the area circumscribed by state borders in the United States, I think Argus' remark on the danger of focusing on numbers as opposed to area of countries experiencing national records is correct. Really, the message is in the statistical bulge in new national high temperature records captured by individual thermometer networks running for many decades. Take away the boundaries and the message is the same, only the network becomes larger I can't read Masters' mind but I suspect he was simply alluding to the broad areal nature of unusual heat extremes this year. Maps transcending national boundaries are a better way to express the concept. Extended quibbling over inconsequential errors in summaries seems like a pointless distraction when the simple statistics are so surprising. -
JMurphy at 01:53 AM on 17 August 2010NASA-GISS: July 2010-- What global warming looks like
Argus wrote : "On the other hand, USA is also a large nation. No national (or state) heat record was set (so far) in 2010, so 0% of USA is counted." Are you sure ? I found this, just for July : It was the hottest July on record in both Rhode Island and Delaware. New Jersey just missed their hottest July, coming in at #2. Thirteen other states had their top 10 hottest July on record. This is indicated in the map above by those states with numbers higher than 106. July 2010: Records and Notables - Weather.com That led to the NOAA report for July : The persistence of this pattern over the last several months has resulted in the warmest May-July on record for several east coast states from South Carolina to New Hampshire. Then, I thought, rather than post anymore, perhaps I should ask you to post your evidence for that lack of "national (or state) heat record[s]". Do you have any ? -
Doug Bostrom at 01:50 AM on 17 August 2010Of satellites and temperatures
That's a fascinating post, BP, but I think most us following this topic already were aware that microwave temperature soundings are not the equivalent of sticking a thermometer into a roast. The clue is in the use of the word "derivation" thousands of times in scholarly works on the subject. Let's assume for the sake of argument that something's wrong w/microwave temperature soundings, freeing us to assess the impact of such a problem on the issue we're discussing here. An assessment of the gravity of an error here would seem to hinge on two questions: --What is the value or relevance of absolute accuracy w/respect to detecting a trend in temperature? --Is there an underlying error in the various methods used to derive temperature from microwave radiance that introduces a secular trend in the readings? I suggest that absolute accuracy is not relevant. If there's a substantial issue it would be an error producing a trend artifact. Is there? -
michael sweet at 00:44 AM on 17 August 2010NASA-GISS: July 2010-- What global warming looks like
Argus, Dr Masters tracks national records. By giving a % of land area he summarizes the data. I find that metric helpful. I recognize the units are not the same size and are not uniform. I think he has found a useful sumary of the data he has. If you don't find it helpful you are welcome to analyize the data and provide a better metric. Criticizing someone who has done the work without providing an alternate method of analysis does not advance understanding at all. -
JMurphy at 00:20 AM on 17 August 2010Did global warming stop in 1998? (basic version)
Arkadiusz Semczyszak wrote : "Solomon: It shows that we shouldn't over-interpret the results from a few years one way or another." I doubt if you will find many here who would disagree with that but, unfortunately, most so-called skeptics use such 'over-interpretations' as a basis for their beliefs. By the way, could you post a link to that quote from Solomon ? Also, that paper has been discussed on this site before (here, where you only made the briefest of interventions), and the pertinent statement about it is this : The paper doesn't draw any conclusions regarding cause, stating that it's not clear whether the water vapor changes are caused by a climate feedback or decadal variability (eg - linked to El Nino Southern Oscillation). The radiative forcing changes (Figure 3 above) indicate that the overall effect from stratospheric water vapor is that of warming. The cooling period consists of a stepwise drop around 2000 followed by a resumption of the warming effect. This seems to speak against the possibility of a negative feedback. -
Arkadiusz Semczyszak at 23:28 PM on 16 August 2010Did global warming stop in 1998? (basic version)
Solomon: It shows that we shouldn't over-interpret the results from a few years one way or another. -
Eric (skeptic) at 22:27 PM on 16 August 2010It hasn't warmed since 1998
In post 61, sailrick projects temperatures based on 2 or 3 times warming feedback of water vapor on top of the increase from CO2 (sensitivity). Sailrick claims a 30 year delay of temperature rise to CO2 increases. Did the oceans expand enough over 30 years to show that kind of heat storage? Finally sailrick acknowledges that extremes are increasing. But that means that the negative feedback is already kicking in (even before it should). Catastrophic warming from water vapor feedback (multiples of 2 or 3) only works if the water vapor is evenly distributed, not concentrated so as to produce record rains. -
Arkadiusz Semczyszak at 22:20 PM on 16 August 2010Did global warming stop in 1998? (basic version)
"w tym kontekście" - "in this context", of course, sorry -
Arkadiusz Semczyszak at 22:17 PM on 16 August 2010Did global warming stop in 1998? (basic version)
“... like the effects of the El Nino ocean current or sunspot activity -- not by cherry-picking single points.” “The slope of NCDC (NOAA) for the past 13 years indicates a warming of a mere 0.08°C although the graph ends during the ongoing El Nino.” I recommend of this very interesting analysis. Contributions of Stratospheric Water Vapor to Decadal Changes in the Rate of Global Warming: “However, the trend in global surface temperatures has been nearly FLAT since the late 1990s despite continuing increases in the forcing due to the sum of the well-mixed greenhouse gases (CO2, CH4, halocarbons, and N2O), raising questions regarding the understanding of forced climate change, its drivers, the parameters that define natural internal variability, and how fully these terms are represented in climate models.” “the decline in stratospheric water vapor after 2000 should be expected to have significantly contributed to the flattening of the global warming trend in the past decade, and stratospheric water increases may also have acted to steepen the observed warming trend in the 1990s.” That, however, even if the warming is still present, this is it: "Flattening" ... because “stratospheric water vapor ...” ... but on the “stratospheric water vapor” we have no influence. Here you have the greatest impact Quasi Biennial Oscillation. Because the QBO affects [short wave radiation] ozone - steam - high clouds. In this way (short wave radiation), we “arrive” at: “Oceans for instance -- because of their heat-storage abilities ...” from Victor de Vries comment - on this website - The role of the Sun “Another point is that shortwave radiation penetrates deeper in the ocean as longwave radiation does (this effect gives the typical blue light in deep waters).” “The oceans absorb most solar energy in the tropics. The small zenit-angle results not only in a high net radiation but also in a deeper penetration of UV-light, and the ozone layer is thinner around the equator.” Very interesting (w tym kontekście) is the change in temperature in the tropics:
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