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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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Comments 131651 to 131700:

  1. There is no consensus
    Austerlitz Thanks for the link. I have posted it at the LiveScience website in an argument that I'm having with one of the NASA guys who isn't a climatologist. Not being a scientist it's hard to be taken seriously so I appreciate the link.
  2. There is no consensus
    Quietman, Here is another scientist who writes some compelling arguments against the theory: http://www.theaustralian.news.com.au/story/0,25197,24036736-7583,00.html I have not checked his credentials; however, I find his arguments convincing. Of course, the Inquisition will dismiss him, as the consensus has already spoken.
  3. Arctic sea ice melt - natural or man-made?
    Somewhat belated: Antarctic sea ice: http://psc.apl.washington.edu/zhang/Pubs/Zhang_Antarctic_20-11-2515.pdf From the Abstract: "The model shows that an increase in surface air temperature and downward longwave radiation results in an increase in the upper-ocean temperature and a decrease in sea ice growth, leading to a decrease in salt rejection from ice, in the upper-ocean salinity, and in the upper-ocean density. The reduced salt rejection and upper-ocean density and the enhanced thermohaline stratification tend to suppress convective overturning, leading to a decrease in the upward ocean heat transport and the ocean heat flux available to melt sea ice. The ice melting from ocean heat flux decreases faster than the ice growth does in the weakly stratified Southern Ocean, leading to an increase in the net ice production and hence an increase in ice mass. This mechanism is the main reason why the Antarctic sea ice has increased in spite of warming conditions both above and below during the period 1979–2004 and the extended period 1948–2004." In other words, a less dense surface layer reduces heat convection from below, which outweighs the increased warming from above. I little known fact: satellite observations began in 1972/1973 for the Arctic/Antarctic. But they aren't as sophisticated as subsequent measurements, and there is a gap in from 1976 to 1978 which is filled with more conventional observational data. However, the recent increase in SH sea ice doesn't match what it was in the early '70s, and there is proxy data showing a large loss starting mid century, but that is disputed. SH Sea Ice: http://cce.890m.com/changes/images/sh-extent.jpg The global trend is clearly down: http://cce.890m.com/changes/images/global-extent.jpg Also, kurt, the '30s were not warmer than current temperatures. In the US, they were similar to today, but global temperatures in the '30s were nowhere close to what they are presently.
  4. We're heading into an ice age
    should've been: "... is basically as high as it gets ..."
  5. We're heading into an ice age
    Quietman: That's simply not true. The glacial cycles of the last 450'000 years have consisted of long periods of slow cooling, followed by rapid warming. (http://commons.wikimedia.org/wiki/Image:Ice_Age_Temperature.png - please note that present day is to the left). This rapid warming is believed to be started by small changes in solar forcing (see Milankovitch cycles: http://en.wikipedia.org/wiki/Milankovitch_cycles) which is enough to start positive feedback spirals: warmer -> more greenhouse gases -> even warmer... Since we've recently come out of an glacial period, temperature is basically is as it gets and should be slowly decreasing (on a long timescale) until we reach the next glacial period. But instead, anthropogenic releases of greenhouse gases have started the process of warming. The amount of released GHG so far is enough to keep the planet warming for a long time (but of course, with possible micro trends of cooling) and we've soon reached a level where positive feedback spirals kick in, meaning that temperature will continue to rise even if we would stop our own releases of GHG.
  6. There is no consensus
    Austerlitz The blog that you gave the URL for was interesting but I found the actual APS newsletter even more interesting.
  7. There is no consensus
    As a Ph.D. scientist, I can attest to the fact there is no consensus among scientists on global warming. So much so, that the American Physical Society has opened debate on the matter. http://www.dailytech.com/Myth+of+Consensus+Explodes+APS+Opens+Global+Warming+Debate/article12403.htm But facts like these seldom get in the way of religious fanatics, and anthropogenic global warming is a religion.
  8. Volcanoes emit more CO2 than humans
    Buried Volcano Discovered in Antarctica By Dave Mosher, LiveScience Staff Writer 20 January 2008: “This eruption occurred close to Pine Island Glacier on the West Antarctic Ice Sheet," Vaughan said. "The flow of this glacier towards the coast has speeded up in recent decades, and it may be possible that heat from the volcano has caused some of that acceleration."
  9. Glaciers are growing
    John This is a strange claim: Global warming causing California glacier to grow (Wednesday, July 9, 2008) "the seven glaciers on Shasta, part of the Cascade mountains in northern California, seem to be benefiting from the warming ocean"
  10. The Mystery of the Vanishing Ocean Heat
    This article from Live Science may explain a little: Seas Striped With Newfound Currents By Brendan Borrell, 14 July 2008
  11. Cartoon about global warming alarmism
    LAI: My dear Sir, Worstall's logic and Hazlitt's logic certainly can't both be "sound" at the same time, because they happen to contradict each other. Worstall thinks more jobs is bad, Hazlitt thinks more jobs is good. I think you may need to revise your idea of what constitutes "sound" "logic".
  12. Arctic sea ice melt - natural or man-made?
    Granted, I have not read all of the comments at this posting, but I have read many of them, and I keep seeing ones that say the world is experiencing unusual warming. Professor Syun-Ichi Akasfu, who studies sea ice and weather, makes a compelling case using peer-reviewed articles that any warming we have seen in recent times is in line with warming that we would expect to see as we recover from the Little Ice Age. Would someone who is prophesier of catastrophic global warming please comment on the case he makes. A paper that he wrote on the subject is "Is the Earth still recovering from the 'Little Ice Age'? : A possible cause of global warming." As for me I don't believe in the catastrophic claims at all. I believe it's all fear-mongering, led by people and groups with political and financial ends in mind or by those who jump on bandwagons without sufficient evidence or who simply scare easily. The fact that the recent temperature measurements of the oceans show them to be cooling slightly in recent years, not heating up, is just one of many reasons that I don't believe this is true, along with the fact that the warmest decade of the last century was the 1930s and the fact that before temperatures stopped rising in about 2003, the world had just hit its 3,000-year average temperature. I also find it a bit amusing that at an earlier posting at this site, the authors go to lots of trouble to show that increased ice creation in the Antarctic is a regional anomaly, while at this posting they want us to believe that ice melting in the Arctic is not a regional anomaly. Again, someone please read the professor paper and comment on the whole argument and all of his proof; don't just try to key on some little nuance so that you can ignore the big picture. Thank you and have a great and hopefully warm day! Here in Wisconsin, we are finally experiencing some summer-like temperatures.
    Response: The various points you make are covered at the following pages: Obviously increasing Antarctic sea ice is a regional anomaly because the Southern Ocean is warming faster than the rest of the oceans of the world. As for Arctic sea ice, the article on this page makes the point that the recent dramatic drop in sea ice was also a regional anomaly - superimposed on the long term trend of falling sea ice. There's your big picture.
  13. Dan Pangburn at 00:56 AM on 9 July 2008
    It hasn't warmed since 1998
    Compared to the average 1998 through 2007: The average for the first 5 months of 2008 is 0.16°C colder according to Hadley's HADcrut3, and 0.10°C colder according to NOAA while the atmospheric carbon dioxide level continues its rise. Climate history shows that added atmospheric carbon dioxide has not had any significant influence on average global temperature. See graphs of NOAA and other credible data (all with source websites given) at http://www.middlebury.net/op-ed/pangburn.html at four different time scales up to 150,000 ybp.
  14. It's the sun
    tlewellen Many of us posting comments are just laymen as well. But because John allows us to put links to reference material it is a great place to learn a lot more about climate change. But like any blog, don't believe everything you read. Like John says at the top of the home page - skepticism is healthy.
  15. There is no consensus
    paledriver I was rereading your post #65. Would you consider the description below qualified in climatology? "He obtained a B.A. in Physics and Mathematics with highest distinction in 1963, an M.S. in Astronomy in 1965 and a Ph.D. in Physics, in 1967, all three degrees from the University of Iowa."
  16. There is no consensus
    paledriver I'm not a scientist either, but as a research engineer I made much use of the scientific process. It does not matter how many believe a particular hypothesis is true, only the one that turns out to be right, regardless of how many backers it had. Working in the private sector, I had a lot of trouble getting some of my papers past managers who did not have a clue as to what I was talking about and believed otherwise, but once in the design staff's hands they understood and acted immediately (I have a lot of experience side-stepping managers). Let me give you a very good and reletively recent example: The late Dr. Rhodes Fairbridge studied the oceans for many years and determined that the sealevel rose and fell in cycles. It was named the Fairbridge cycle in DERISION because the consensus said he was wrong. It is now recognized to be correct and the consensus wrong. The hypothesis published in a science magazine in 1966 is the one explained by Dr. Riscard Mackey in his eulogy for Dr. Fairbridge. Again he went against the consensus but I think that he was correct. It was the only climate prediction made (last summer) that turned out to be correct thus far (it predicted low sunspot activity and cooling starting in 2008) and the IPCC, it seems, is finally paying some attention.
  17. There is no consensus
    Quietman, you argument about consensus doesn't relate. In science, truth wins out over time. And over time, as more and more data comes in, the consensus on this matter grows. As I've said, I'm just a layman but I know that much at least.
  18. Volcanoes emit more CO2 than humans
    Sorry the subject of comment 9 is the south Atlantic, although it also affects the south pacific.
  19. There is no consensus
    paledriver p.s. I put that link in 62 to see if anyone could tell me if it was the same as discussed previously.
  20. There is no consensus
    paledriver I went back and read it again. It seems to be from the same organization but it also seems to be a different petition, they mention one in 2001 with 19k+ signers, and then they talk about 31k signers with 9k+ PHDs. It does not really mean anything one way or the other as I don't accept consensus as proof of anything, if I did I would be Hindu or Buddist (I'm sure one of those two have a consensus).
  21. There is no consensus
    paledriver I have been following along but I did not realize that it was the same one because of the number and date. So this petition is still circulating?
  22. There is no consensus
    Qietman, if you go to the link provided by #62 you'll find it's the same old Petition Project by OISM. If you go to my posts 4,8,12,14 and 28 (to begin with) you'll get a start on that petition and the "inhofe 400".
  23. There is no consensus
    Will Nitschke There have been several updates to the link that you posted. Below is the latest one only. U.S. Senate Report: Over 400 Prominent Scientists Disputed Man-Made Global Warming Claims in 2007 Senate Report Debunks "Consensus" UPDATE: More and more scientists continue to declare their dissent of the ‘consensus.’ (LINK) Climate Skeptics Reveal ‘Horror Stories’ of Scientific Suppression (NYC Climate Conference Report - Part One of Reports) March 6, 2008 "Many prominent scientists participating and attending were very impressed by the New York City climate conference. Hurricane researcher and Meteorologist Stanley B. Goldenberg of NOAA (National Oceanic and Atmospheric Administration) in Miami praised the Heartland Instituted sponsored conference. “The fact is that this conference is evidence that there are numerous respected, established and in many cases world-renowned scientists who have done careful research in various areas of ‘climate change’ that sharply differ with the [UN] IPCC results,” Goldenberg told the New York Times."
  24. There is no consensus
    paledriver I was under the impression that this was a newer petition. Are you saying that this is the same one as the 20k scientists earlier in this thread?
  25. Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????
    Quietman If I were to chose a collarobator to make a discovery, I might choose you. Open minds tend to prevail in science. What I see that is difficult about understanding the climate is that there appear to be 10 variables, all dependant on the others. In basic Physics, theories are easy to test because there were only a few variables, all easily measured and constrained. No such situation exists with climate and weather. The complexities are more like String theory or Chaos theory. And, Quiteman, you are correct about the sites. Most sites are more Political Science, that science. Tom
  26. It's the sun
    Quietman, BriMan,TruthSeeker, et al As just a curious layman, it is good to see that the banter and debate on this site is broad and deep. This kind of debate in the press and Congress would do our nation some good. GW, I assume, will be like much of science through history. It is seldom complete, even when we think it is. Whether it was the Catholic Church's belief that the earth was the center of the Universe, or a long held believe that there were only four elements, or even that for some time most believed that there were 24 chromosomes. Good scientists hold to the facts in front of them. Great scientists keep looking when the science does not match the facts. Reading your inciteful remarks, I can conclude we are still very short of good data and great science. There is still so much to debate.
  27. There is no consensus
    in response to number 62. this was when they claimes 17,000.....".. took a sample of 30 of the 1,400 signatories claiming to hold a Ph.D. in a climate-related science. Of the 26 we were able to identify in various databases, 11 said they still agreed with the petition -- one was an active climate researcher, two others had relevant expertise, and eight signed based on an informal evaluation. Six said they would not sign the petition today, three did not remember any such petition, one had died, and five did not answer repeated messages. Crudely extrapolating, the petition supporters include a core of about 200 climate researchers -- a respectable number, though rather a small fraction of the climatological community.". this from when it was first released......"The Marshall Institute co-sponsored with the OISM a deceptive campaign -- known as the Petition Project -- to undermine and discredit the scientific authority of the IPCC and to oppose the Kyoto Protocol. Early in the spring of 1998, thousands of scientists around the country received a mass mailing urging them to sign a petition calling on the government to reject the Kyoto Protocol. The petition was accompanied by other pieces including an article formatted to mimic the journal of the National Academy of Sciences. Subsequent research revealed that the article had not been peer-reviewed, nor published, nor even accepted for publication in that journal and the Academy released a strong statement disclaiming any connection to this effort and reaffirming the reality of climate change. The Petition resurfaced in 2001.". and more...."Of 100 names googled, only about 2 percent turn out to be scientists with any training relevant to climatology, usually physics. A small number -- about 15 percent -- were other kinds of scientists or physicians, but with no relevant training. Several in this overall pool of scientists were quite elderly. The remainder were either people with no scientific credentials whatsoever (40 percent), or names that did not appear in the search -- highly improbable nowadays if indeed such people existed." so the petition is clearly a fabrication.
  28. It's the sun
    Bri-Man To bring you up to speed (at least on this site) the 70's are referenced because in the mid to late 70's the solar forcing stopped following the temperature line. Their argument, which is that of the IPCC, is that CO2 induced AGW explains the increases from 1975 on. Those of us skeptical of this argument have several positions, mine is vulcanism and plate tectonics which have been more active since the full alignment in 1976. The most recently active thread is "Arctic sea ice melt - natural or man-made?" and the discussion is somewhat heated.
  29. It's the sun
    Stop listening to the media and paid celebrities. They have no sort of degree in science and are just reading from a script. This has all stemed from "Yellow Science." It used to be that we listened to the scientists from both sides of the argument. Now we don't even listen to them at all, we listen to the media, politicians and paid celebrities, none which have any clue of what they are talking about. It's a shame that the scientists on the other side of the fence don't get the same main stream media attention that Al Gore does. But the reason for this is very simple and clear....MONEY. Over 50 Billion dollars has been spent world wide for Global Warming research. These scientists don't even have to come up with anything significant to get paid, they just have to sign there name with a little PhD right next to it. Big corporations have also made a killing selling "Green" products. Governments world wide will never let these scientists get world wide attention either because they can't admit they have been DUPPED into believeing that the sky was falling and that they just spent billions of your tax dollars on it. Keep an open mind, look at """"ALL"""" of the science and then draw your conclusions.
  30. It's the sun
    Why does this site keep referencing the 70's? The planet if over 4 billion years old and has been chaning ever since. You are sitting here talking about the last few hundred years like they have been of any kind of significance in the last 4 billion. It's just a spec, not even that really. More drastic changes have happened (climate wise) in Earths history then the industrial revolution. Does anybody else think that this is a form of "Vanity?" Short of nuclear fallout, I don't think that we could put a dent in this planets way of working. I do think however that pollution is bad for us humans, and we should look at that more then global destruction.
  31. It's the sun
    Remeber what Einstein said, "No amount of experimentation can ever prove me right; a single experiment can prove me wrong."
  32. Arctic sea ice melt - natural or man-made?
    What about this statement from BRET STEPHENS piece in WSJ published on July 1st? "The Arctic ice cap may be thinning, but the extent of Antarctic sea ice has been expanding for years." Is this true, if so how does that support global warming? http://online.wsj.com/article/SB121486841811817591.html?mod=fpa_mostpop
  33. Arctic sea ice melt - natural or man-made?
    What about this statement from BRET STEPHENS piece in WSJ published on July 1st? "The Arctic ice cap may be thinning, but the extent of Antarctic sea ice has been expanding for years." Is this true, if so how does that support global warming? http://online.wsj.com/article/SB121486841811817591.html?mod=fpa_mostpop
  34. Arctic sea ice melt - natural or man-made?
    What about this statement from BRET STEPHENS piece in WSJ published on July 1st? "The Arctic ice cap may be thinning, but the extent of Antarctic sea ice has been expanding for years." Is this true, if so how does that support global warming? http://online.wsj.com/article/SB121486841811817591.html?mod=fpa_mostpop
  35. Arctic sea ice melt - natural or man-made?
    What about this statement from BRET STEPHENS piece in WSJ published on July 1st? "The Arctic ice cap may be thinning, but the extent of Antarctic sea ice has been expanding for years." Is this true, if so how does that support global warming? http://online.wsj.com/article/SB121486841811817591.html?mod=fpa_mostpop
  36. barry schwarz at 14:52 PM on 1 July 2008
    It hasn't warmed since 1998
    Hadley's own analysis for the trend 1998 - 2007 concludes; "A simple mathematical calculation of the temperature change over the latest decade (1998-2007) alone shows a continued warming of 0.1 °C per decade." http://www.metoffice.gov.uk/corporate/pressoffice/myths/2.html
  37. We're heading into an ice age
    Actually we can't head into an ice age at this point in time because we are already in one. Technically this is an interglacial period within the current ice age, ie. this is not "Earth Normal" climate, which is much hotter. Interglacial means "between glacations" and is about as unstable a climate as possible on this planet. That is assuming that it is an interglacial rather than the ice age ending (far worse for us). It also assumes that another glacation will occur. Looking at graphs of prior interglacials and glacations there is a particular constant: it warms slowly for thousands of years then cools rapidly (it looks very similar to a sawtooth inventory graph). Another fact is that CO2 has been very high when it suddenly became very cold (it did nothing to stop the glacations). So be afraid, be very afraid.
  38. Arctic sea ice melt - natural or man-made?
    Phillippe, my apologies, I think I was looking at 2000 not 2001 or 2002, your graph makes it pretty clear that the sea ice seems to be heading for another low year(though I am not sure that the spring melt is all that atypical). chris, "O.K., but nobody says that CO2 can explain the state of the cryosphere in toto! Two points: (A) As well as CO2, there are the other man-made greenhouse gases (methane, nitrous oxides, CFC's, tropospheric ozone), there are man-made aerosols, there are variations in solar outputs, volcanic eruptions.... (B) One then has to consider how various wind and ocean currents distribute thermal energy around the world. The net thermal imbalance (that gives us global-scale warming or cooling) is a summation of all of (A): " But that is essentially my point, if regional climates can be influenced by something besides the net thermal imbalance, then answering (a), as you did above is premature at best unless all you are saying is that the slight temperature increase of the last couple decades has had an impact of the sea ice(something that probably no one disagrees with). You seemed to suggest that one can explain the recent trend solely in terms of CO2. I'll accept your numbers for the SH ice extent from the beginning of satellite measurement (I don't have the inclination to try to read the graphs that closely), but just eyeballing the numbers since 2000 does give an overall increase in the SH summer ice extent as around +1 million, which puts the most recent trend in the same ballpark magnitude (though of opposite sign) as trend in summer sea ice in the NH(even higher if you start it earlier). Given a cyclically changing climate(like the one we have) one can prove pretty much any point one wants to by selectively choosing one's starting point. My point is that the recent(ie the last 10 yrs) changes in *global* sea ice can't be explained by CO2. Cheers, :)
  39. barry schwarz at 18:50 PM on 30 June 2008
    It hasn't warmed since 1998
    Hadley's own analysis for the trend 1998 - 2007 concludes; "A simple mathematical calculation of the temperature change over the latest decade (1998-2007) alone shows a continued warming of 0.1 °C per decade." http://www.metoffice.gov.uk/corporate/pressoffice/myths/2.html
  40. barry schwarz at 14:13 PM on 30 June 2008
    It hasn't warmed since 1998
    Hadley's own analysis for the trend 1998 - 2007 concludes; "A simple mathematical calculation of the temperature change over the latest decade (1998-2007) alone shows a continued warming of 0.1 °C per decade." http://www.metoffice.gov.uk/corporate/pressoffice/myths/2.html
  41. Climate's changed before
    A change or two in climate history has recently been revealed indicating change happens faster than thought: Fossils Found In Tibet Revise History Of Elevation, Climate ScienceDaily (June 12, 2008) — About 15,000 feet up on Tibet's desolate Himalayan-Tibetan Plateau, an international research team led by Florida State University geologist Yang Wang was surprised to find thick layers of ancient lake sediment filled with plant, fish and animal fossils typical of far lower elevations and warmer, wetter climates. Greenland Ice Core Analysis Shows Drastic Climate Change Near End Of Last Ice Age ScienceDaily (June 19, 2008) — Information gleaned from a Greenland ice core by an international science team shows that two huge Northern Hemisphere temperature spikes prior to the close of the last ice age some 11,500 years ago were tied to fundamental shifts in atmospheric circulation.
    Response: This would indicate that climate is more sensitive than realised which means the climate response to CO2 forcing will be greater than current estimations.
  42. Arctic sea ice melt - natural or man-made?
    As for evidence of increased vulcanism that are causing hot spots and more active El Ninos, etc. Surprisingly Rapid Changes In Earth’s Core Discovered - ScienceDaily (June 20, 2008) — The movements in the liquid part of the Earth’s core are changing surprisingly quickly, and this affects the Earth’s magnetic field, according to new research from DTU Space. Olsen et al. Rapidly changing flows in the Earth's core (I have posted the abstract in the volcano thread).
  43. Volcanoes emit more CO2 than humans
    The current work on vulcanism in the south Pacific: Olsen et al. Rapidly changing flows in the Earth’s core. Nature Geoscience 1, 390 - 394 (2008) Published online: 18 May 2008 | doi:10.1038/ngeo203 Subject Category: Geomagnetism, palaeomagnetism and core processes Rapidly changing flows in the Earth's core Nils Olsen & Mioara Mandea A large part of the Earth's magnetic field is generated by fluid motion in the molten outer core. As a result of continuous satellite measurements since 1999, the core magnetic field and its recent variations can now be described with a high resolution in space and time. These data have recently been used to investigate small-scale core flow, but no advantage has yet been taken of the improved temporal resolution, partly because the filtering effect of the electrically conducting mantle was assumed to mask short-period magnetic variations.. Here we show that changes in the magnetic field occurring over only a few months, indicative of fluid flow at the top of the core, can in fact be resolved. Using nine years of magnetic field data obtained by satellites as well as Earth-based observatories, we determine the temporal changes in the core magnetic field and flow in the core. We find that the core flow is spatially localized and involves rapid variations over a few months, with surprisingly large local accelerations. Our results suggest that short-term fluctuations of the core magnetic field are robust features of rapid core dynamics and should be considered in the development of future numerical models of the geodynamo. Danish National Space Center/DTU and Niels Bohr Institute at Copenhagen University, Juliane Maries Vej 30, 2100 Copenhagen, Denmark GeoForschungsZentrum Potsdam, Telegrafenberg, 14473 Potsdam, Germany Correspondence to: Nils Olsen1 e-mail: nio@space.dtu.dk
  44. Arctic sea ice melt - natural or man-made?
    "Resonant interactions between solar activity and climate" Tobias, S.M.; Weiss, N.O. Journal of Climate. Vol. 13, no. 21, pp. 3745-3759. Nov. 2000 Solar magnetic activity exhibits chaotically modulated cycles with a mean period of 11 yr, which are responsible for slight variations in solar luminosity and modulation of the solar wind, while the earth’s atmosphere and oceans support oscillations with many different frequencies. Although there are several mechanisms that might couple solar variability with climate, there is, as yet, no compelling evidence that a direct forcing is sufficiently effective to drive climatic change. In many nonlinear systems resonant coupling allows weak forcing to have a dramatic effect. An idealized model is considered, in which the solar dynamo and the climate are represented by low-order systems, each of which in isolation supports chaotic oscillations. The climate is represented by the Lorenz equations: solutions oscillate about either of two fixed points, representing warm and cold states, flipping sporadically between them. The effect of a weak nonlinear input from the dynamo to the climate that tends to push it toward the warm state is computed. This input has a significant effect when the ‘typical frequencies’ of each system are in resonance. The solution is now asymmetric, with the warm state preferred. The degree of asymmetry is less than might be anticipated, because resonant forcing extends the duration of oscillations about either state, and so increases the timescale for flipping. The presence of grand minima in the solar output leads to complicated intermittent behaviour in the climate. Consequently, the results of frequency analysis are sensitive to the duration of time series that is used. It is clear that the resonance provides a powerful mechanism for amplifying climate forcing by solar activity. Surface warming by the solar cycle as revealed by the composite mean difference projection Charles D. Camp and Ka Kit Tung Received 29 March 2007; revised 15 May 2007; accepted 14 June 2007; published 18 July 2007. Geophys. Res. Lett., 34, L14703, doi:10.1029/2007GL030207. ABSTRACT [1] By projecting surface temperature data (1959?2004) onto the spatial structure obtained objectively from the composite mean difference between solar max and solar min years, we obtain a global warming signal of almost 0.2_K attributable to the 11-year solar cycle. The statistical significance of such a globally coherent solar response at the surface is established for the first time. Citation: Camp, C. D., and K. K. Tung (2007), Surface warming by the solar cycle as revealed by the composite mean difference projection, Geophys. Res. Lett., 34, L14703, doi:10.1029/2007GL030207. Conclusion [11] We propose that spatial information be used to filter the surface-temperature data to obtain a cleaner solar-cycle response. At the global scales, an objectively determined spatial filter can be constructed using the composite difference between the solar-max years and the solar-min years. This filter effectively removes the shorter interannual variations, such as from ENSO. We obtained a globally averaged warming of almost 0.2_K during solar max as compared to solar min, somewhat larger than previously reported. More importantly, we have established that the global-temperature response to the solar cycle is statistically significant at over 95% confidence level. The spatial pattern of the warming is also of interest, and shows the polar amplification expected also for the greenhouse-warming problem. The method used here, the CMD Projection, is one of two methods we have tried that take advantage of the spatial information, the other method being the LDA method. Although not as optimal as the LDA method, the CMD Projection possesses most of the advantages of the former while being much simpler to understand and implement. As it turns out, the spatial patterns deduced by the two different methods are very close to each other. However, the LDA method yields a more accurate estimate of the solar-cycle response in the sense that its error bar is only half as large. [12] We will argue in a separate paper that the observed warming is caused mostly by the radiative heating (TSI minus the 15% absorbed by ozone in the stratosphere), when taking into account the positive climate feedbacks (a factor of 2?3) also expected for the greenhouse warming problem. Solar-Cycle Warming at the Earth?s Surface and an Observational Determination of Climate Sensitivity. By Ka-Kit Tung and Charles D. Camp Department of Applied Mathematics, University of Washington, Seattle Washington, USA Journal of Geophysical Research, submitted. ABSTRACT The total solar irradiance (TSI) has been measured by orbiting satellites since 1978 to vary on an 11-year cycle by about 0.07%. From solar min to solar max, the TSI reaching the earth?s surface increases at a rate comparable to the radiative heating due to a 1% per year increase in greenhouse gases, and will probably add, during the next five to six years in the advancing phase of Solar Cycle 24, almost 0.2 ?K to the globally-averaged temperature, thus doubling the amount of transient global warming expected from greenhouse warming alone. Deducing the resulting pattern of warming at the earth?s surface promises insights into how our climate reacts to known radiative forcing, and yields an independent measure of climate sensitivity based on instrumental records. This model-independent, observationally-obtained climate sensitivity is equivalent to a global double-CO2 warming of 2.3 -4.1 ?K at equilibrium, at 95% confidence level. The problem of solar-cycle response is interesting in its own right, for it is one of the rare natural global phenomena that have not yet been successfully explained. 7. Conclusion Using NCEP reanalysis data that span four and a half solar cycles, we have obtained the spatial pattern over the globe which best separates the solar-max years from the solar-min years, and established that this coherent global pattern is statistically significant using a Monte-Carlo test. The pattern shows a global warming of the Earth?s surface of about 0.2 ?K, with larger warming over the polar regions than over the tropics, and larger over continents than over the oceans. It is also established that the global warming of the surface is related to the 11-year solar cycle, in particular to its TSI, at over 95% confidence level. Since the solar-forcing variability has been measured by satellites, we therefore now know both the forcing and the response (assuming cause and effect). This information is then used to deduce the climate sensitivity. Since the equilibrium response should be larger than the periodic response measured, the periodic solar-cycle response measurements yields a lower bound on the equilibrium climate sensitivity that is equivalent to a global warming of 2.3 ?K at doubled CO2. A 95% confidence interval is estimated to be 2.3-4.1 ?K. This range is established independent of models. 11-Year solar cycle in the stratosphere extracted by the empirical mode decomposition method K.T. Coughlin, K.K. Tung University of Washington, Box 352420, Seattle, WA 98195, USA Received 19 October 2002; received in revised form 26 February 2003; accepted 26 February 2003 Advances in Space Research 34 (2004) 323?329 Abstract We apply a novel method to extract the solar cycle signal from stratospheric data. An alternative to traditional analysis is a nonlinear empirical mode decomposition (EMD) method. This method is adaptive and therefore highly efficient at identifying embedded structures, even those with small amplitudes. Using this analysis, the geopotential height in the Northern Hemisphere can be completely decomposed into five non-stationary temporal modes including an annual cycle, a QBO signal, an ENSO-like mode, a solar cycle signal and a trend. High correlations with the sunspot cycle unambiguously establish that the fourth mode is an 11-year solar cycle signal. 5. Conclusion A clear solar cycle signal is observed in the 30 mb geopotential height using the nonlinear, non-stationary EMD method. The total geopotential height at 30 mb is spatially averaged over all longitudes and from 20N to 90N. No specific grouping of the data is used in this analysis. The entire timeseries is completely decomposed into five modes and a trend. Using a Monte-Carlo simulation, the power in each mode is compared to the power in 500 decompositions of random noise. The fourth mode is found to have an average power far above the noise level and therefore is a significant signal. The correlation between this signal and the solar cycle proxy is 0.70 which is also significant given our estimation of the degrees of freedom in the mode. Using a regression with AR errors, the significance of the correlation is verified. The result is both a statistically and visually convincing solar cycle signal in the total 30 mb geopotential height. Further analysis at lower levels and with latitudinal variations will be presented in our forthcoming paper.
  45. Arctic sea ice melt - natural or man-made?
    And yes Philippe, I have very little respect for the post JFK education standards in the U.S. with the "no one left behind" concept used to reduce the passing average to the lowest common denominator. On the other hand I have the greatest respect for those who have overcome this handicap.
  46. Arctic sea ice melt - natural or man-made?
    Philippe Sorry, I was under the impression that you understood the sarcasm. My issue is back to a previously discussed point: why is it that Fairbridge "hypothesis" has not been thoroughly investigated by planetary and solar scentists?
  47. Philippe Chantreau at 09:00 AM on 29 June 2008
    Arctic sea ice melt - natural or man-made?
    Your condescending tone was ill-used against me, I did not direct anything of the sort a you. You bring us back to a previously discussed point: why is it that Fairbridge "hypothesis" has not been thoroughly investigated by planetary and solar scentists? As for your post #103, it's your opinion. Everybody has one. Many of these scientists are as old or older than you. It now sounds like you're being condescending toward an entire scientific and academic community.
  48. Arctic sea ice melt - natural or man-made?
    p.s. Nothing about this planet is well understood, despite claims to the contrary. Our young scientists have much to learn.
  49. Arctic sea ice melt - natural or man-made?
    Philippe Thank you, I am quite pleased that you recognized my complaint. Just because I am retired does not mean that I have time on my hands, albeit more than I had as an engineer. In an agrarian community winters are slow but this is planting and pest control season. If you are interested I have posts with links under the volcano thread. While vulcanism is still discounted by many scientists, more is discovered every day, and if Dr. Fairbridge was correct in his solar hypothesis, more evidence will be found soon, thanks to modern satellites. The most recent two are in the south Pacific.
  50. Arctic sea ice melt - natural or man-made?
    Shawnet, re: "Since there is the same amount of CO2 in the SH as the NH, CO2 cant explain the state of the cryosphere in toto." O.K., but nobody says that CO2 can explain the state of the cryosphere in toto! Two points: (A) As well as CO2, there are the other man-made greenhouse gases (methane, nitrous oxides, CFC's, tropospheric ozone), there are man-made aerosols, there are variations in solar outputs, volcanic eruptions.... (B) One then has to consider how various wind and ocean currents distribute thermal energy around the world. The net thermal imbalance (that gives us global-scale warming or cooling) is a summation of all of (A): -CO2 dominates -other greenhouse gases make a significant contribution -aerosols are nett cooling -solar variation has made no significant contribution since the late 50's (perhaps a slight cooling one overall) -volcanic eruptions make sporadic cooling "pulses" etc. (the numbers for many of these contributions are in the Ramanathan and Carmichael paper leebert cited - see posts #39/#48) So global warming IS largely about greenhouse gases, the full effects of which are attenuated by our aerosol emissions. (B) relates to the manner in which this excess thermal energy is distributed around the world. It doesn't depend on the location of CO2, and the fact that the CO2 concentrations are the same in the Nrthn. and Srthn. hemisphere, is a red-herring with respect to the distribution of thermal energy (excess heat) measured at the Earth's surface. After all, land warms faster than the oceans since the oceans provide a massive sink which buffers surface warming. So obviously the Nrthn. hemisphere warms faster than the Srthn. Major ocean currents carry heat from the low latitudes to the high Nrthn latitudes (Arctic!), whereas ocean currents in the deep Srthn. hemisphere "insulate" the Antarctic from heat absorbed in the low latitudes….. That's all pretty well understood (see post #66). Since the time of detailed satellite observation the Antarctic sea ice hasn't changed very much at all: a small trend of around +12,000 km2 per year for the summer sea ice extent: http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.area.south.jpg ...whereas during the same period, the Arctic summer sea ice trend is around -85,000 km2 per year (more like -131,000 km2 per year since 2000-ish). http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.area.jpg Note that the data presented at the site you linked to in post #59 is a little bit misleading, since, first, it's considering only a single year, secondly it gives the sea ice extent at one particular snapshot in time (Jan 31st 2008!), and thirdly it doesn't really compare like with like. For example the concern is for SUMMER ice extent since this is the period in which solar irradiation directly affects surface warming through albedo effects from sea ice melting (and black carbon too!). Thus it's more appropriate to compare sea ice extent in late summer in the Arctic (Aug-Sept) with sea ice extent in late summer in the Antarctic (Feb-March). Note btw, that the Antarctic sea ice extent was apparently larger in the period 1900-1960 than now[*], so it too has undergone some attenuation, but in the last 20-ish years it's been pretty steady. But that's not unexpected given our understanding of the manner in which thermal energy from low latitudes distributes to higher latitudes. [*] N. A. Rayner et al. (2003) Global analyses of sea surface temperature, sea ice, and night marine air temperature since the late nineteenth century; Journal Of Geophysical Research, 108, NO. D14, 4407.

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