The Spectator Is Hot for Global Warming Denial
If there is any credit due to the monstrous legacy of Britain's Margaret Thatcher it is that she -- with her background in science -- always accepted the reality of man-made global warming. The British Conservative Party never took the route of denial that Republicans in the U.S or the Liberal Party in Australia followed. The same cannot be said, alas, for Britain's predominantly right-wing press which has given a great deal of space to Global Warming time-wasting as it once did to denying the link between HIV and AIDS.
This week, the Spectator (a bit like a British counterpart to the National Review) has a front page splash: "Relax: Global Warming is All a Myth" with James Delingpole interviewing Australian denier, Ian Plimer, publicising his new book.
Global warming denial is not a set of scientific ideas -- it's a collection of bogus factoids which have a zombie-like ability to keep returning to life, seeking new brains to feed on no matter how many times they are shot down.
To give an example. Someone, somewhere at one time decided to claim that the carbon dioxide (CO2 -- our leading contribution to heat-trapping gases in the atmosphere) of volcanoes is greater than that of human industry and transport.
This claim is unambiguously false. Man-made carbon emissions exceed those of volcanoes by a factor of 130.
But no matter. When Martin Durkin's film The Great Global Warming Swindle was broadcast on the UK's Channel 4, there it was. Complete with a little cartoon of a volcano belching out CO2. In one of many edits for errors and distortions, the volcano claim was removed prior to the film's DVD release.
Now Ian Plimer has written a book, Heaven and Earth, getting a lot of people very excited, and guess what? The volcano factoid is back! Back from the dead, volcanoes are celebrated by deniers one again.
The process goes like this:
1. Global Warming Denier makes claim
2. Claim is comprehensively, indisputably debunked
3. Claim is withdrawn, while Denier publicly continues to assert they are the new Galileo and their critics are religious fanatics with no regard for facts
4. New Global Warming Denier makes exactly the same claim as if previous debate never happened
And on and on. Apparently forever. No matter how often the volcano factoid -- just one of many -- is shown to be false, it will come back. Maybe in a new book, film, newspaper article, bogus scientific paper produced by a think tank funded by industry, from the mouth of a TV pundit, or from a politician. It will survive in a fact-free vacuum, ready to be reborn as required.
The deniers constantly accuse those who understand the basic science of global warming enough to realize they are full of it, of being intolerant, fanatical adherents of dogma. But it is pretty clear who is, and who isn't, susceptible to changing their minds in the face of the facts.
Most of us would wish the deniers were right. The trouble is, the evidence is entirely against them. Unable make an argument, they will latch on to anything -- anything at all -- and reassure themselves with the same zombie factoids all over again.
Imagine a Universe Where Nothing Ever Had Any Consequences: Wouldn't That Be Nice?
Delingpole begins, "Imagine how wonderful the world be if man-made global warming were just a figment of Al Gore's imagination." Yes indeed, and imagine too how wonderful it would be if magical winged horses flew down from the sky each morning and made you breakfast and only Al Gore tried to stop them with a pernicious, envious flying-pony tax.
The ad hominem attacks on Al Gore are an obsessive constant of anti-environmentalist writing. Now Gore has become an ambassador for the science to the global public. But he didn't come up with it himself. His slide-show lecture is a collection of claims made by scientists with the relevant expertise. The message is theirs, not Gore's. The basic theory of Anthropogenic Global Warming was proposed by Swedish scientist Svante Arrhenius in 1895. He's the guy you want. Him and the tens of thousands of climate scientists whose work followed from it.
Research claims in science are submitted in the form of a paper to established journals where they are then critiqued by others in the field before publication. This process allows old ideas to be challenged, but only after new ones have been tested. It's a process designed to remove fraudulent or obviously weak claims. New ideas are welcome -- but they have to prove themselves.
It's fairly common in any field to have leading scientists disagree about the data and its interpretation. But with the basic facts of global warming -- that burning fossil fuels releases gases that trap more heat in the atmosphere on a scale great enough to change climate, there is no dispute. None. There is not a single peer-reviewed paper among hundreds.
Ian Plimer -- a geologist, not a climatologist -- can challenge the overwhelming scientific consensus if he wants. He just has to write a real scientific paper and send it to an established journal for peer review. Writing a book full of bogus claims for the benefit of readers who don't know anything about science is not "going to change forever the way we think about climate change."
So far, no peer-reviewed from paper from Pilmer. Or any other global warming denier. Why? Because their arguments don't stand up to 30 seconds' scrutiny from anyone who gives it real thought, let alone climatologists.
Mmmmm, Carbon Dioxide...Yum!
Delingpole's article would not be complete without more than its fair share of zombie factoids, apparently taken from Plimer's book.
One favorite is the claim that "CO2 is not a pollutant but a plant food." So if we lock ourselves up in a room full of CO2 in order to celebrate its life-giving qualities, what will happen as we breathe in this fine plant food?
Well done to those aged nine and up who learned at school that you would suffocate and die. In some contexts, CO2 is a pollutant. Oh, and it's not actually a food.
Not that either point is relevant -- what matters is that CO2 traps heat in the atmosphere. A lot of it traps more heat. Lots of extra heat is a potential problem for those who live on Planet Earth. Talking about the wonders of CO2 in some other, irrelevant context is a painfully transparent attempt to sound science-y while distracting your reader.
Also in there we have the claim: "...the CO2 in the atmosphere -- to which human activity contributes the tiniest fraction -- is only 0.001 per cent of the total CO2 held in the oceans, surface, rocks, air, soils and life."
Returning to the facts -- before the emergence of human industry, there were 280 parts per million (ppm) of CO2 in the atmosphere. Now, as the US National Oceanic and Atmospheric Administration informs us, there are 387 ppm. Not "the tiniest fraction," but a significant jump -- the predicted result of pouring billions of tonnes of the stuff into the atmosphere every year at an ever-increasing rate.
Plimer and Delingpole are propounding the withdrawn-from-their-backsides Law of How Small Things Don't Have Major Effects. It's an idea that has no real basis in science and relies of emotional demagoguery -- look at those tiny parts per million! They're so small! They wouldn't hurt a fly! The testable, provable effectiveness of small amounts of CO2 molecules in trapping heat is swept away using irrelevant appeals to ignorance.
The same logic would lead us to conclude that viruses and bacteria are harmless because they are very, very small. Why, the anthrax virus must be only a tiny fraction of your body weight. Therefore, it is safe to eat, as proven by percentages.
Global Warming Doesn't Exist And It's Not Even That Bad Anyway
Plimer and Delingpole, like most professional deniers, are men of contradictions, as we have already seen. At the beginning of the piece, Pilmer explains why his background as a geologist is even better in understanding the climate than a climatologist, who actually studies it: "They're only interested in the last 150 years. Our time frame is 4,567 million years. So what they're doing is the equivalent of trying to extrapolate the plot of Casblanca from one tiny bit of the love scene. And you can't. It doesn't work."
OOOH! Smackdown! How could anyone be so foolish as to make conclusions out of a mere 150 years of data, when the planet's climate has been developing and changing over billions of years?
Well, apparently Plimer can, within three paragraphs:
"There is no problem with global warming. It stopped in 1998."
Climatologists can't work in a time frame of 150 years, says Plimer, but Plimer can work in a time frame of the 11 years since 1998. Never mind, it will still get published in the Spectator.
While we're at it, are those claims actually true? Do climatologists work in a frame of 150 years? Did global warming stop in 1998? Well, no. And also no.
Climatologists have used a number of methods to learn how climate has changed over longer time periods and shown that the current warming exceeds anything humanity has experienced in at least a thousand years. Among them, Michael Mann famously produced a graph of temperature in the Northern Hemisphere over the last thousand years and deniers have dedicated a great deal of their time failing to discredit it. How could Delingpole have forgotten the denier nemesis, the hated, wicked, tricksy, false and demonstrably accurate "Hockey-Stick Graph"?
As for 1998 -- that was an unusually hot year, exceeding even the temperature of the previous record-holder way back in 1997. Average temperatures in 1998 were exacerbated by the short-term effects of a record-breaking El Nino in the Pacific Ocean, as well as the long-term trend towards global warming. Nonetheless, global average temperatures have continued to rise since 1997 and NASA recorded fractionally higher temperatures in 2005 -- when there was no additional El Nino effect. A graph makes the upward trend, and the denier cherry-picking, clear.
Medium and short term trends (such as the ocean cycle) can work both ways -- they can cool the planet down for a while, even as CO2 and other greenhouse gases continue to accumulate in the atmosphere. But they don't effect the long-term trend as greenhouse gases accumulate.
If climate scientists had ever said, "Because global warming is taking place, it will never be cold anywhere, ever again and each day will be hotter than the last", then the observation that some years have been cooler than 1998 would matter. Since they don't, loudly and often, there are no excuses for the "It's-cold-today-so-global-warming-is-a-fraud!" time-wasters.
Global Warming Doesn't Exist and Historically It's Always Been Fun for Everyone
Global warming is part of a natural cycle, nothing to do with people. Also, global warming has stopped. Global warming is associated with nice things like warm, sunny days and wine-growing. Also, the world is getting cooler. The ice caps have melted before anyway. Also, global warming has caused mass extinctions in the past quite naturally.
All of those claims appear in Delingpole's piece. Is there anyone who can't see the contradiction between them? Global warming is not happening, but it also is happening and it's a natural process that shouldn't bother anybody. And it isn't happening. And it happens all the time in Earth's history! And it stopped in 1998!
The one fact that those in deep denial have is that the climate of the Earth does indeed change over time without man-made causes and has done many, many times in the planet's history. It's not a magical process, though. The climate changes because of a forcing. A forcing can be any of a number of things -- including changes in solar activity and variations in the Earth's orbit and rotation.
The evidence shows now that human beings, by releasing the energy stored in fossil fuels into the atmosphere, can also create a climate forcing. The only forcing that explains current warming. There isn't a contradiction between these facts.
Now if the global warming currently taking place were not caused by human emissions of greenhouse gases, it would still be a very serious matter and cause for, yes, alarm. But the deniers' main interest -- their only consistency -- is to say anything that will prevent people from thinking that industry or government need to act. They have a particular need to ridicule the thought that global warming is a potential destroyer of the lives of hundreds of millions of people. You will never come across a denier who says that global warming is not man-made but nonetheless worrying and we should prepare for it.
They are in the difficult and multi-contradictory position of insisting that climate change is a natural process which is always going on and also there is no need to worry.
Usually the trick is to look at various moments of past natural climate change and pick out cutesy-wutesy anecdotes like how in the Mediaeval Warm Period (MWP), people in the North of England used to grow grapes for wine or how during the Little Ice Age around the 17th-19th centuries, people in London used to hold ice fairs on the frozen River Thames, which currently does not freeze over at all.
Delingpole does not disappoint those on the look out for these zombie-stories:
"...the Earth's warmer periods -- such as when the Romans grew grapes and citrus trees as far north as Hadrian's Wall [in England] -- were times of wealth and plenty."
Sigh. The actual scientists at RealClimate.org persist in pointing out that, actually, wine is still made in the North of England, and it wins international prizes for its quality. Readers could play a drinking game where you whip out a bottle of English wine whenever you hear a denier make this fatuous claim yet again.
But over in Central America you can look at the still-standing ruins of the once-mighty Mayan civilization, its glorious cities abandoned during the MWP. There isn't a consensus on this, but some scientists have claimed that the period of warming triggered centuries-long droughts in their part of the world, not wealth and plenty -- a suggestion you won't hear deniers mention during discussions of natural climate change. Perhaps the Mayans all left Central America for England where they could grow wine and live happily ever after.
And the MWP was limited in its scope -- it affected the North Atlantic region, not the entire globe.
In the same paragraph of factoids where Delingpole lists wine from the North of England, he also states breezily that, "extinctions of life are normal". So just relax, guys, and enjoy your extinction!
Nasty Rich Socialists Want to Stop the Poor From Enjoying Global Environmental Catastrophe
Finally, and inevitably, we have a consideration of the mysterious and dark motives of environmentalists, particularly the nasty rich socialists who want stop the world's poor from enjoying environmental catastrophe.
Delingpole's article covers the life of Plimer growing up in working-class Australia, a part that interests me because my own Dad grew up there at the same time. It didn't turn my Dad into a global warming denier, so it can't be especially relevant. Unless this is part of some inverted, bizarre Class War which is contrasting Plimer's working-class authenticity with the supposed wealth and privilege of members of Greenpeace. Which, of course, it is.
The point of this biographical detail is that environmentalism is the product of the disordered minds of the rich, those terrible "metropolitan liberals" who live in cities and are liberal, proving their infamy for everyone to see. American readers will know this script.
"Eco-guilt is a first-world luxury," Plimer asserts, arguing that some people he has met in rural Turkey and Iran have no time for this science nonsense. Real working-class people want to improve their lives by burning more fossil fuels. They must not be held back by hateful rich left-wingers who envy rich people and are rich, seeking to impose their fanciful notions of environmental aesthetics enviously on the poor. (NB: I am not caricaturing that argument in the slightest -- read it yourself and see.)
This is a particularly obnoxious lie, another complete reversal of the truth. Global warming is a major concern of the world's poor who will be (and are being) hit hardest by it. It is denial that is a luxury for those who can afford to protect themselves from environmental catastrophes from New Orleans to India to Darfur. Here is Johann Hari (declaration -- a friend of mine), interviewing a Bangladeshi teenager in a country where the effects of global warming are obvious and ominous:
I clambered back on to one of the 42 school-boats in this area. Young children were in the front chanting the alphabet, and teenagers at the back were browsing through the books. I asked a 16-year-old boy called Mohammed Palosh Ali what he was reading about, and he said, "Global warming." I felt a small jolt. He was the first person to spontaneously raise global warming with me. Can you tell me what that is? "The climate is being changed by carbon dioxide," he said. "This is a gas that traps heat. So if there is more of it, then the ice in the north of the world melts and our seas rise here."I asked if he had seen this warming in his own life. "Of course! The floods in 1998 and 2002 were worse than anything in my grandfather's life. We couldn't get any drinking water, so the dirty water I drank made me very sick. The shit from the toilet pits had risen up and was floating in the water, but we still had to drink it. We put tablets in it but it was still disgusting. What else could we do?"
Eco-guilt isn't a luxury. It's the normal, non-sociopathic emotion you get when you realize what the effects of our carbon-intense lifestyles are on others.
There are no arguments in Plimer's article that stand up. His book has already been doused elsewhere in the acid of scrutiny by people who know what they're talking about. It has not fared well.
But it won't stop the arguments it contains from doing their work. Too many people, really, really do not want to believe that life on Earth is changing and that drastic changes in our economy and society will be necessary, possibly costing industry a lot of money. That's why the story of the volcanoes that produce more CO2 than burned fossil fuels lives on and are destined to be repeated over and over.
Expect too, to hear about wine in Northern England again, how CO2 is only a small part of the atmosphere, that climate change is cyclical and unthreatening but also world-changing, that CO2 is good for plants so we can put it in the atmosphere without consequences, that global warming stopped in 1998. I'm only surprised they left out the one about the time when all scientists in the 70s in the world thought there was going to be an ice age except for the majority who didn't.
And when every one of those is knocked down again by the facts, you'll hear deniers proudly boast that they are bold truth-tellers who refuse to tow the party line (watch out for that one in the comments below!), wrongly persecuted for their courageous stance by the mindless sheep who accept the overwhelming weight of the evidence. When this appears in the national press, it merits a stern, clear response.
Meanwhile, global average temperatures and man-made greenhouse gases both rise inexorably.
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From the Christy paper:
"The recent trends of TMean calculated from global datasets do not agree with our results for this cell. As shown in Table 2, the 1979–2004 TMean trend of the central cell as produced by HadCRUT3v, CRUTEM3v, and GISS (0.31, 0.47, and 0.35 deg C/decade, respectively) are markedly inconsistent with all of the time series for that cell constructed in this study. Evidently, the main signal used by HadCRUT3v for this cell since 1979 is derived from the single Nairobi, Kenya, station at Jomo Kenyatta Airport (P. Jones 2004, personal communication). Our unadjusted time series for this site does indeed show significant warming since 1979 (0.25 deg C/decade), but the higher trend is not corroborated by the many nearby stations used in our analysis. Such differences were also found in central California (Christy et al. 2006) and northern Alabama (Christy 2002), where our more comprehensive reconstructions were on average about 0.1 deg C/decade more negative in the cells covering those areas versus values for the cell from global databases."
Here's the second:
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F2008JCLI2726.1&ct=1
Surface Temperature Variations in East Africa and Possible Causes
"Surface temperatures have been observed in East Africa for more than 100 yr, but heretofore have not been subject to a rigorous climate analysis. To pursue this goal monthly averages of maximum (TMax), minimum (TMin), and mean (TMean) temperatures were obtained for Kenya and Tanzania from several sources....Results for the most data-rich 5° cell, which includes Nairobi, Mount Kilimanjaro, and Mount Kenya, indicate that since 1905, and even recently, the trend of TMax is not significantly different from zero. However, TMin results suggest an accelerating temperature rise...Significant human development of the surface may be responsible for the rising TMin while having little impact on TMax in East Africa. This indicates that time series of TMax and TMin should become separate variables in the study of long-term changes."
Two new papers for you.
The first suggests that Arctic warming may be due to the Atlantic Multi-decadal Oscillation, rather than AGW:
http://www.agu.org/pubs/crossref/2009/2009GL038777.shtml
Arctic air temperature change amplification and the Atlantic Multidecadal Oscillation
Petr Chylek, Chris K. Folland, Glen Lesins, Manvendra K. Dubey & Muyin Wang
"Understanding Arctic temperature variability is essential for assessing possible future melting of the Greenland ice sheet, Arctic sea ice and Arctic permafrost. Temperature trend reversals in 1940 and 1970 separate two Arctic warming periods (1910–1940 and 1970–2008) by a significant 1940–1970 cooling period. Analyzing temperature records of the Arctic meteorological stations we find that (a) the Arctic amplification (ratio of the Arctic to global temperature trends) is not a constant but varies in time on a multi-decadal time scale, (b) the Arctic warming from 1910–1940 proceeded at a significantly faster rate than the current 1970–2008 warming, and (c) the Arctic temperature changes are highly correlated with the Atlantic Multi-decadal Oscillation (AMO) suggesting the Atlantic Ocean thermohaline circulation is linked to the Arctic temperature variability on a multi-decadal time scale."
Note that Chris Folland is an author of the third IPCC report.
kruddler, if you're still around. I found something else on that phony study by Professor Carter on the Influence of the Southern Oscillation.
"The New Zealand Climate Science Coalition is a group of scientists, mainly from New Zealand, whose stated aim is to "represent accurately, and without prejudice, facts regarding climate change; to provide considered opinion on matters related to both natural and human-caused climate effects; and to comment on the economic and socio-political consequences of climate change". They hold the position that "climate science is not settled, that the world is not on the brink of a man-made global warming catastrophe"."
The chairman of the group is Jack Welch, a former Navy Rear Admiral.
"The founding members were coal chemist Vincent R. Gray; geologist Robert M. Carter and researcher at the Marine Geophysical Laboratory at James Cook University in Australia; environmental campaigner David Bellamy; Augie Auer, atmospheric scientist and meteorologist; ...
"The coalition lobbied government to institute a Royal Commission on Climate Change, which was refused on the grounds that the "majority of climate scientists in the world agree that there is no longer any doubt our climate is changing due to human activity"."
"The organisation has encountered some criticism, with suggestions that their aim to increase the level of media coverage to allow equal press for climate-change dissent actually creates an illusion of greater dissent than truly exists."
http://en.wikipedia.org/wiki/New_Zealand_Climate_Science_Coalition
Hi RP,
I haven't been able to devote more than a few minutes here and there to these threads for the past couple of days which is a pity, since I've got loads of papers to share on most facets of the causes and effects of global warming :( Unfortunately, my time constraints are likely to continue for the next few days (We're gearing up at work towards a swine flu clinical trial).
Well done finding some facts on Professor Carter's affiliations; the scientific criticisms of the data presented in his paper will be interesting to read and more pertinent to the discussion of the science. I'm sure there are many scientists like Carter who are biased either way.
I came across this site today, which contains a historical record of storminess from Armagh (a county in Northern Ireland if you didn't already know) from the late 18th century to today. It fits in well with many of the papers I've read which suggest that storms have decreased in general over the past 50 years.
http://climate.arm.ac.uk/publications/The_Storminess_Record_from_Armagh_Observatory_Dr4.htm
I'll try my best to respond to your comments.
That's OK, I thought I was responding to your comments.
Last response on paper.....
In their paper, they are just pointing out a correlation bewteen ENSO and temperature change, which all climate scientists know of. They are not even trying to explain the reason for any temperature trend. The best criticism is that the oceans merely transport the heat and do not create it.
"Water is not a primary source of heat, it is merely a transport and possibly a storage mechanism. If the SOI is transferring more heat to the Troposphere, where is that heat coming from? was it in the ocean which would be cooling as a result? somewhere else? where are the numbers? how does this explain the increase in the Earth’s temperature? or are the authors suggesting a violation of the Laws of thermodynamics?"
"The perfectly obvious explanation is global warming is also warming the ocean (it being part of the globe … a little fyi for the authors who apparently did not know that), which stores and transports it."
http://greenfyre.wordpress.com/2009/07/24/is-our-whole-dissembly-appeared/
There are problems with methodology.
http://tamino.wordpress.com/2009/07/24/old-news/
Authors BOB Carter:
http://www.realclimate.org/wiki/index.php?title=Robert_Carter
Chris de Freitas
http://www.desmogblog.com/chris-dde-freitas
McLean
http://bravenewclimate.com/2008/09/09/spot-the-recycled-denial-iv-%E2%80%93-climate-case-built-on-thin-foundation/
I'm not sure of the publication status- this might not be an accepted manuscript as yet:
http://arxiv.org/abs/0907.1650
Structural break models of climatic regime-shifts: claims and forecasts
Submitted to the International Journal of Forecasting on 5 July 2009
it is interesting because the authors of your study say: "Quirk (2009) proposed that the increase in Australian temperature from 1910 to the present was largely confined to a regime-shift in the Pacific Decadal Oscillation (PDO) between 1976 and 1979."
I just wonder how a temperature increase since 1910 can be related to a PDO shift between 1976 and 1979? It does not seem logically in that the temperature rise began 66 years before the PDO change in 1976?
Further, the PDO may have more of an effect in Southern Hemisphere.
"The PDO has been described by some as a long-lived El Niño-like pattern of Pacific climate variability.... A growing body of evidence highlights a strong tendency for PDO impacts in the Southern Hemisphere, with important surface climate anomalies over the mid-latitude South Pacific Ocean, Australia and South America....Several independent studies find evidence for just two full PDO cycles in the past century: “cool” PDO regimes prevailed from 1890–1924 and again from 1947–1976, while “warm” PDO regimes dominated from 1925–1946 and from 1977 through the mid-1990's."
http://www.springerlink.com/content/5xm9ngv5fn5dc2r7/
It may be hard to predict.
"These results support the hypothesis that the PDO is not a dynamical mode, but arises from the superposition of sea surface temperature fluctuations with different dynamical origins."
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2FJCLI3527.1
And being cyclical it goes from a cooler pattern to a warmer one and back again.
I think overall PDO needs further study!
Fresh off the press (haven't been able to access the full pdf yet):
Journal of Geophysical Research Atmospheres
Received 16 December 2008; accepted 14 May 2009; published 23 July 2009.
Influence of the Southern Oscillation on tropospheric temperature
"Time series for the Southern Oscillation Index (SOI) and global tropospheric temperature anomalies (GTTA) are compared for the 1958−2008 period. GTTA are represented by data from satellite microwave sensing units (MSU) for the period 1980–2008 and from radiosondes (RATPAC) for 1958–2008....Overall the results suggest that the Southern Oscillation exercises a consistently dominant influence on mean global temperature, with a maximum effect in the tropics, except for periods when equatorial volcanism causes ad hoc cooling. That mean global tropospheric temperature has for the last 50 years fallen and risen in close accord with the SOI of 5–7 months earlier shows the potential of natural forcing mechanisms to account for most of the temperature variation."
http://www.agu.org/pubs/crossref/2009/2008JD011637.shtml
I have noted that the authors use the word "potential of natural forcing" so their conclusions are hypothesised based on their statistical data. Interesting nonetheless. Not the most prestigious journal I've ever read.
Some of these I have to get back to.
"Not the most prestigious journal I've ever read." This study is entirely bogus. The others you have presented so far gave been excellent, but the author of this one is a professional skeptic working for the energy industry.
"Professor Carter, whose background is in marine geology, appears to have little, if any, standing in the Australian climate science community." He is a well known climate change skeptic.
Carter was a speaker at the International Conference on Climate Change (2009), organized by the Heartland Institute think tank. Carter is also listed as a speaker for the Heartland Institute's June 2009 Third International Conference on Climate Change. (Heartland published the bogus list of 500 scientists who disagreed with anthropogenic climate change that included dead people, ficticious people, and totally distorted real scientist's conclusions. Most immediately demanded to be removed from list.)
"In March 2007 the Sydney Morning Herald reported that "Professor Carter told the Herald yesterday the Intergovernmental Panel on Climate Change had uncovered no evidence the warming of the planet was caused by human activity. He said the role of peer review in scientific literature was overstressed, and whether or not a scientist had been funded by the fossil fuel industry was irrelevant to the validity of research. 'I don't think it is the point whether or not you are paid by the coal or petroleum industry,' said Professor Carter. 'I will address the evidence.'"
(cont.)
Carter is a member of the right-wing think tank the Institute of Public Affairs, and a founding member of the Australian Environment Foundation, a front group set up by the Institute of Public Affairs."
"The Institute of Public Affairs (IPA) is a right-wing, corporate funded think tank based in Melbourne...The IPA key policy positions include: advocacy for privatisation and deregulation; attacks on the positions of unions and non-government organisations; support of assimilationist indigenous policy (cf. the Bennelong Society) and refutation of the science involved with environmental issues such as climate change."
"For all their talk of 'transparency' though, the IPA has beem embroiled in controversy over failure to disclose funders of its work. In June 2004 it was revealed that Australia's largest irrgation company, Murray Irrigation Limited, contributed $40,000 to the IPA. However, Marohasy did not disclose the donation to the committee.IPA executive director Mike Nahan stated the donation did not affect the organisation's position."
Here is a very interesting page that sums up these natural events like ENSO, PDO, and solar forcing.
http://www.ask.com/bar?q=Influence+of+the+Southern+Oscillation++study+is+bogus&page=4&qsrc=2417&ab=2&u=http%3A%2F%2Fclimateprogress.org%2F2008%2F07%2F08%2Fyes-the-globe-is-warming-but-how-fast%2F
Another discussion of natural forcings:
http://www.cru.uea.ac.uk/cru/info/causecc/
http://www.ncdc.noaa.gov/oa/climate/globalwarming.html
I see
No.7:
Lombard et al. (2005) conclude from their studies that “we simply cannot extrapolate sea level into the past or the future using satellite altimetry alone. Even the 50 years of global ocean temperature data we possess are insufficient to tell us much about the degree of global warming that may have occurred over the past half-century, as any long-term increase in global sea level that may have been caused by the
temperature increase is dwarfed by decadal-scale variability."
Lombard, A., Cazenave, A., Le Traon, P.-Y. and Ishii, M. 2005. Contribution of thermal expansion to present-day sea-level change revisited. Global and Planetary Change 47: 1-16.
I'm pooped! I look forward to your replies.
Yes, so you are starting to see the importance of longer time trends to scientists before they announce definitive trends. But sea levels have been rising longer than the last 50 years. According to NOAA, "The sea level has been steadily rising since 1900 at a rate of 1 to 2.5 millimeters per year. In fact, since 1992 new methods of satellite altimetry using the TOPEX/Poseidon satellite indicate a rate of rise of 3 millimeters per year."
http://sos.noaa.gov/datasets/Ocean/sea_level.html
Therefore, if they want to announce a trend, it is fine with me. but they are just being cautious as scientists should be.
No. 6:
Holgate derived a mean global sea-level history from 177 coastal tide gauge records that spanned the period 1955-1998. Holgate also chose nine much longer high-quality records from around the world. Based on the reconstructed 1904-2003 mean global sea-level history of the world,, he calculated that the mean rate of global sea-level rise was “larger in the early part of the last century (2.03 ± 0.35 mm/year 1904-1953), in comparison with the latter part (1.45 ± 0.34 mm/year 1954-2003).”
Holgate, S.J. 2007. On the decadal rates of sea level change during the twentieth century. Geophysical Research Letters 34.
Holgate, S.J. and Woodworth, P.L. 2004. Evidence for enhanced coastal sea level rise during the 1990s. Geophysical Research Letters 31.
In his first paper you referenced, he only used nine tidal stations for his inferences: "Nine long and nearly continuous sea level records were chosen from around the world to explore rates of change in sea level for 1904–2003"
According to Wiki, "Because of the limited geographic coverage of these records, it is not obvious whether the apparent decadal fluctuations represent true variations in global sea level or merely variations across regions that are not resolved."
In his secong paper, he said "Sea level rise over the last 55 years is estimated to have
been 1.7 ± 0.2 mm yr1, based upon 177 tide gauges divided
into 13 regions with near global coverage and using a Glacial
Isostatic Adjustment (GIA) model to correct for land
movements."
Then, "Global sea level is believed to have risen at a rate
of 1–2 mm yr1 during the past 100 years, based on
evidence from the sparse global tide gauge data set . On the other hand, analysis of near-global,
precise radar altimetry has suggested a rate of rise nearer to
3 mm yr1 for the past decade."
Over the period January 1993 to December 2002 the
tide gauges, corrected for GIA using the second approach,
provide a global average rate of 4.0 mm yr1 with a range
of 6.8 to 12.4 mm yr1 across the 13 regions.
http://www.imedea.uib.es/goifis/OTROS/VANIMEDAT/documentos/intranet/Bibliography/Holgate_coastal_SLrise_2005.pdf
The earlier paper uses the 177 tide gauges. To answer your query, in the more recent paper, Holgate used the 9 high quality gauges spanning to see if their combined mean progression over the 1955-1998 period was similar enough to the concomitant mean sea-level history of the 177 stations to employ the mean nine-station record as a reasonable representation of mean global sea-level history for the much longer period stretching from 1904 to 2003. In comparing the sea-level histories derived from the two datasets, Holgate found their mean rates-of-rise were indeed similar over the second half of the twentieth century; this observation thus implied that “a few high quality records from around the world can be used to examine large spatial-scale decadal variability as well as many
gauges from each region are able to do.”
No. 4:
White et al. (2005) compared estimates of coastal and global averaged sea level for 1950 to 2000. Their results suggested “no significant increase in the rate of sea-level rise during this 51-year period.”
White, N.J., Church, J.A. and Gregory, J.M. 2005. Coastal and global averaged sea level rise for 1950 to 2000. Geophysical Research Letters 32
No. 5:
Jevrejeva et al (2006) produced mean global sea level (gsl) and gsl rate-of-rise (gsl rate) curves from 1850-2000. Their data suggest no acceleration of sea-level rise since the end of the Little Ice Age. They say that “global sea-level rise is irregular and varies greatly over time,” but “it is apparent that rates in the 1920-1945 period are likely to be as large as today’s.”
Jevrejeva, S., Grinsted, A., Moore, J.C. and Holgate, S. 2006. Nonlinear trends and multiyear cycles in sea level records. Journal of Geophysical Research 111.
These take time and I will have to get to some tomorrow. I did answer your post about sunspots on the next page, though. Hope your daughter is not so "crook" anymore and feeling better!
Yep, she's bonzer today.
"However, our results show that global sea level rise is irregular and varies greatly over time, it is apparent that rates in the 1920–1945 period are likely to be as large as today’s. Nevertheless, considerable uncertainties remain."
"However, the main source for the uncertainties in sea level studies using tide gauge records still remain: poor historical distribution of tide gauges, lack of the data from Southern Hemisphere (Africa and Antarctica), the GIA corrections used, and localized tectonic activity."
So to sum up, I think what is unique about this paper is that it identifies a period from 1920 to 1945 with sea level rise as great as after the 1990's. I do not know what the explanation is.
"However, our results show that global sea level rise is irregular and varies greatly over time, it is apparent that rates in the 1920"1945 period are likely to be as large as today"s. Nevertheless, considerable uncertainties remain."
"However, the main source for the uncertainties in sea level studies using tide gauge records still remain: poor historical distribution of tide gauges, lack of the data from Southern Hemisphere (Africa and Antarctica), the GIA corrections used, and localized tectonic activity."
So to sum up, I think what is unique about this paper is that it identifies a period from 1920 to 1945 with sea level rise as great as after the 1990's. I do not know what the explanation is.
Remember that although new satellite measurements said that sea level rise was increasing, "the Third Assessment Report (TAR) from the IPCC does not consider this a significant acceleration, stating, "No significant acceleration in the rate of sea level rise during the 20th century has been detected."
The University of Colorado at Boulder describes problems with tidal gauge measurements of sea level. They often measure glacier rebound which, as you know, describes a process where the continent rebounds from the weight of glacial retreat. U. of C.-Boulder says "Tide gauges may also move vertically with the region as a result of post-glacial rebound, tectonic uplift or crustal subsidence. This greatly complicates the problem of determining global sea level change from tide gauge data. Differences in global sea level estimates from tide gauge data usually reflect the investigator's approach in considering these vertical crustal movements. Tide gauges also monitor meteorological factors that affect sea levels, such as barometric pressure and windspeed, so that these variable factors can be eliminated from long-term assessments of sea level change. Although the global network of tide gauges comprises of a poorly distributed sea level measurement system, it offers the only source of historical, precise, long-term sea level data. Major conclusions from tide gauge data have been that global sea level has risen approximately 10-25 cm during the past century."
http://www.ask.com/bar?q=tidal+gauges+coastal+sea+level+rise&page=1&qsrc=0&ab=0&u=http%3A%2F%2Fsealevel.colorado.edu%2Ftidegauges.php
Church himself states in the paper "A 20th century acceleration in global sea-level rise" Most estimates of 20th century sea-level rise have depended on averaging the rates of rise from the few, long, high-quality tide-gauge records that are available [Douglas, 1991, 2001; Peltier, 2001]. However, these records contain significant decadal variability, obscuring any acceleration [Woodworth, 1990; Douglas, 1992]. Even when a global mean sea level (GMSL) record is known to contain an acceleration (as in numerical models), an acceleration is difficult to detect in an average of a small number of records [Gregory et al., 2001].
He then says "From 1993, the rates of rise estimated from tide gauge and altimeter data (after correction for GIA effects [Douglas and Peltier, 2002]) are about 3 mm yr1." This increase is similar to what satellites observe.
http://people.uncw.edu/tobiasc/Climate%20Change/climate%20change%20readings/Sea%20Level/Church%20and%20White%202004.pdf
According to White et. al. (2005), "The altimeter and the reconstructed sea level trends
are in close agreement for both the global average and the coastal average during the common period (1993 to 2000)........We conclude that if several GIA models are used the best estimate of both global averaged and coastal sea level rise for 1950 to 2000 remains 1.8 ± 0.3 mm yr1 as shown by Church et al. [2004]. The models show an increase in the rate of global average sea level rise during the 20th century but any increase in the 51 year observational record is masked by decadal variability. Gregory et al. [2001] suggest on the basis of model variability that the acceleration might not be detectable given the available sampling by tide gauges."
According to "Nonlinear trends and multiyear cycles in sea level records: "There is no common reference level for the tide gauge records and this provides a problem when stacking records that do not cover the same time periods. .....However, many stations have historically only been measured for some months of the year and an annual cycle in sea level could therefore lead to severe bias."
"However, our results show that global sea level rise is irregular and varies greatly over time, it is apparent that rates in the 1920"1945 period are likely to be as large as today"s. Nevertheless, considerable uncertainties remain."
"However, the main source for the uncertainties in sea level studies using tide gauge records still remain: poor historical distribution of tide gauges, lack of the data from Southern Hemisphere (Africa and Antarctica), the GIA corrections used, and localized tectonic activity."
So to sum up, I think what is unique about this paper is that it identifies a period from 1920 to 1945 with sea level rise as great as after the 1990's. I do not know what the explanation is.
It appears to correlate with the temperature rise over similar dates - see GISS, NCDC surface anomalies; I doubt CO2 is a good explanation since levels rose marginally between 1920-1945.
Cazenave and Nerem (2004) say that “the geocentric rate of global mean sea-level rise over the last decade (1993-2003) is now known to be very accurate, +2.8 ± 0.4 mm/year, as determined from TOPEX/Poseidon and Jason altimeter measurements,” and that “this rate is significantly larger than the historical rate of sea-level change measured by tide gauges during the past decades (in the range of 1-2 mm/year).” However, they then admit “the altimetric rate could still be influenced by decadal variations of sea level unrelated to long-term climate change". In addition, they note that “for the past 50 years, sea-level trends caused by change in ocean heat storage also show high regional variability (which) has led to questions about whether the rate of 20th- century sea-level rise, based on poorly distributed historical tide gauges, is really representative of the true global mean.”
Cazenave, A. and Nerem, R.S. 2004. Present-day sea level change: observations and causes. Reviews of Geophysics 42
Note that this paper was published before that of Hogate (2007), above.
Yes, the scdientists say: "The average rate of sea-level change obtained from tide gauges over the last 50 years is +1.8 mm + or - 0.3 mm yr. In comparison, altimeter measurements from TOPEX/Poseidon and Jason-1 have shown an average rise of since 1993. It is not clear yet whether the larger rate of rise of the last decade reflects acceleration or decadal fluctuation."
So, they need more time to make an assessment. Again, they emphasize the accuracy of the satellite data.
Then they say, "Regional variability in sea-level change, as evidenced by the quasi global coverage of altimeter satellites, appears dominated by non uniform change of thermal expansion. New satellite technologies, such as InSAR, ICESat, and GRACE make significant contributions to understanding sea-level change."
I did not see in the abstract the language you posted about "sea-level trends caused by change in ocean heat storage also show high regional variability (which) has led to questions about whether the rate of 20th- century sea-level rise." We may have a different translation from the original French."
No. 2:
Church et al. (2004) used TOPEX/Poseidon satellite altimeter data together with historical tide gauge data to estimate monthly distributions of large-scale sea-level variability and change over the period 1950-2000. Their resultant “best estimate” of the rate of globally averaged sea- level rise over the last half of the twentieth century was 1.8 ± 0.3 mm/year. They go on to say that “decadal variability in sea level is observed, but to date there is no detectable secular increase in the rate of sea-level rise over the period 1950-2000.” What is more, they reported that no increase in the rate of sea-level rise has been detected for the entire twentieth century.
Church, J.A., White, N.J., Coleman, R., Lambeck, K. and Mitrovica, J.X. 2004. Estimates of the regional distribution of sea level rise over the 1950-2000 period. Journal of Climate 17: 2609-2625.
To sum up on sea level rise, "It is well established that sea level trends obtained from tide gauge records shorter than about 50-60 years are corrupted by interdecadal sea level variation. However, only a fraction (
I'll try again! "It is well established that sea level trends obtained from tide gauge records shorter than about 50-60 years are corrupted by interdecadal sea level variation. However, only a fraction (
Oddly, it will not print my entry. Please see "Global Sea Level Rise: A Determination, Surveys in Geophysics", Bruce C. Douglas, 2004
I mean, "Global Sea Level Rise: A ReDetermination." I am making many mistakes now.
"It is well established that sea level trends obtained from tide gauge records shorter than about 50-60 years are corrupted by interdecadal sea level variation. However, only a fraction (
I've tried to find as many papers as I can on sea level rise. Decide for yourself.
No.1:
Mörner (2004) reports that “the mean eustatic rise in sea level for the period 1850-1930 was of the order of 1.0-1.1 mm/year,” but that “after 1930-40, this rise seems to have stopped.This stasis “lasted, at least, up to the mid-60s.” Thereafter, with the advent of the TOPEX/Poseidon mission, Mörner notes that “the record can be divided into three parts: (1) 1993-1996 with a clear trend of stability, (2) 1997-1998 with a high-amplitude rise and fall recording the ENSO event of these years and (3) 1998-2000 with an irregular record of no clear tendency.” Mörner states that “there is a total absence of any recent ‘acceleration in sea-level rise’ as often claimed by IPCC and related groups.”
Mörner, N.-A. 2004. Estimating future sea level changes from past records. Global and Planetary Change 40: 49- 54.
Perhaps he was looking at different tidal station data than earlier authors. Remember Jevrejeva, S., Grinsted, A., Moore, J.C. and Holgate, S. 2006. Nonlinear trends and multiyear cycles in sea level records. Journal of Geophysical Research 111, identified a strong linear increase in sea levels between 1920 and 1945 and a corresponding one between after 1990. They said: "However, our results show that global sea level rise is irregular and varies greatly over time, it is apparent that rates in the 1920"1945 period are likely to be as large as today"s. Nevertheless, considerable uncertainties remain."
In fact, almost all of the papers agree about an increase after 1990 or so. Remember Cazenave and Nerem (2004) said that "the geocentric rate of global mean sea-level rise over the last decade (1993-2003) is now known to be very accurate, +2.8 � 0.4 mm/year, as determined from TOPEX/Poseidon and Jason altimeter measurements,"
I believe Morner is misstating the findings of the IPCC.
Remember that although new satellite measurements said that sea level rise was increasing, "the Third Assessment Report (TAR) from the IPCC did not consider this a significant acceleration, stating, "No significant acceleration in the rate of sea level rise during the 20th century has been detected."
In fact, in Fourth Assessment Report, the IPCC says, "Increases in sea level are consistent with warming. Global average sea level rose at an average rate of 1.8 [1.3 to 2.3]mm per year over 1961 to 2003 and at an average rate of about 3.1 [2.4 to 3.8]mm per year from 1993 to 2003. Whether this faster rate for 1993 to 2003 reflects decadal variation or an increase in the longer term trend is unclear."
http://www.ipcc.ch/pdf/assessment-report/ar4/syr/ar4_syr.pdf
Here's a recent paper. It's conclusions appear a bit inconclusive.
Atmospheric Carbon Dioxide Concentration Across the Mid-Pleistocene Transition
Bärbel Hönisch,1 N. Gary Hemming,1,2 David Archer,3 Mark Siddall,4 Jerry F. McManus1
"The dominant period of Pleistocene glacial cycles changed during the mid-Pleistocene from
40,000 years to 100,000 years, for as yet unknown reasons. Here we present a 2.1-million-year
record of sea surface partial pressure of CO2 (PCO2), based on boron isotopes in planktic foraminifer
shells, which suggests that the atmospheric partial pressure of CO2 (pCO2) was relatively stable
before the mid-Pleistocene climate transition. Glacial PCO2 was ~31 microatmospheres higher
before the transition (more than 1 million years ago), but interglacial PCO2 was similar to that of
late Pleistocene interglacial cycles (
The rest of the abstract:
" These estimates are consistent with a close linkage between atmospheric CO2 concentration and global climate, but the lack of a gradual decrease in interglacial PCO2 does not support the suggestion that a long-term drawdown of atmospheric CO2 was the main cause of the climate transition."
Science Vol 324 pages 1551-1554 June 19, 2009
This one and the one below I have to get back to.
I could not locate that abstract. According to Wiki, "the Pleistocene is the epoch from 1.8 million to 10 000 years BP covering the world's recent period of repeated glaciations."
"Glaciation in the Pleistocene was a series of glacials and interglacials, stadials and interstadials, mirroring periodic changes in climate. The main factor at work in climate cycling is now believed to be Milankovitch cycles. These are periodic variations in regional solar radiation caused by the sum of many repeating changes in the Earth's motion."
"Milankovitch cycles cannot be the sole factor since they do not explain the start and end of the Pleistocene ice age, or of repeated ice ages. They seem to work best within the Pleistocene, predicting a glaciation once every 100 000 years."
Temperatures and co2 track each other very well at least over the last 400,000 years, as graph on middle of page shows.
http://www.sciencetime.org/blog/?p=95
It's unfortunate that sometimes one has to rely on the authors' word that their conclusions (based on their results) are likely. The main figure in the Honisch paper is a bewildering mass of data points covering several proxies. I've alot of experience deciphering graphs but this was hard to interpret without intimate knowledge of the scientific processes being used. The same applies with much of the detailed physics and computational methods used in the discussions revolving around concepts such as forcing, albedo, irradiance, modelling etc. I hate relying on the word of scientists who may or may not know what they're doing, but have managed to publish peer-reviewed papers that appear technically correct, but are based on only known variables and have inherent uncertainties that may actually be very important. I know of lots of papers published in reputable journals such as Cell, Immunity, Science and Nature but are complete bs. The usual response can often be "We didn't think of that". I'm rambling...time for bed.
It appears before this mid-Pleistocene transition, the Milankovitch cycles did not explain the ice ages as much as a oblique earth orbit around the sun, Before this transition it appears the glaciations may have come and gone every 41 thousand years, instead of 100,000. "The mid-Pleistocene transition (MPT) from obliquity- to eccentricity-forced climate variations has been
extensively documented within the oceanic realm."
http://www.marum.de/Binaries/Binary24647/Heslop_et_al_2002-PPP185.pdf
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V61-3T7F3K9-V&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=cd6784bd7db4706092385df6076bf3a8
"We therefore suggest that the late Pleistocene 100-kyr climatic cycles are likely a nonlinear response to orbital obliquity, although the timing of late Pleistocene 100-kyr climatic cycles and their early forms appears to be paced by eccentricity/precession."
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V61-4R644R7-1&_user=10&_origUdi=B6V61-3T7F3K9-V&_fmt=high&_coverDate=01%2F30%2F2008&_rdoc=1&_orig=article&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=197ce965ad726563c0140c2c12a46b26
There is someone who posts here frequently on climate change named Exusian. He is a real expert and I bet could answer this question. If you run across him keep the question in mind. He has excellent science background. I am sorry, this may be the best I have for now. If I find something later I'll add it.
This study talks about co2 levels and glaciation.
http://www.nature.com/nature/journal/v421/n6920/abs/nature01290.html
Here are several papers contending that CO2 does not correlate with temperature, based on paleoclimactic data:
Rothman (2002) derived a 500-million-year history of the air’s CO2 content. Rothman reports that the CO2 history “exhibits no systematic correspondence with the geologic record of climatic variations at tectonic time scales.”
Rothman, D.H. 2002. Atmospheric carbon dioxide levels for the last 500 million years. Proceedings of the National Academy of Sciences USA 99: 4167-4171.
Pagani et al. (2005) found that about 43 million years ago, the atmosphere’s CO2 concentration was approximately 1400 ppm and the oxygen isotope ratio (a proxy for temperature) was about 1.0 per mil. Then, over the next ten million years, the air’s CO2 concentration experienced three huge oscillations on the order of 1000 ppm from peak to valley. In the first two oscillations, temperature did not appear to respond at all to the change in CO2, exhibiting an uninterrupted slow decline. Following the third rise in CO2, however, temperatures seemed to respond, but in the direction opposite to what the greenhouse theory of global warming predicts, as the rise in CO2 was followed by the sharpest drop in temperature of the entire record.
Pagani, M., Zachos, J.C., Freeman, K.H., Tipple, B. and Bohaty, S. 2005. Marked decline in atmospheric carbon dioxide concentrations during the Paleogene. Science 309: 600-603.
And I've lost two citations showing that the start and finish of the glacial periods of the last few hundred thousand years precedes changes in CO2. They were Fisher et al (1999) and Petit et al (1999).
Very fascinating studies! Regarding the second, I can only access the abstract (perhaps you read the entire study), which says: "The relation between the partial pressure of atmospheric carbon dioxide (pCO2) and Paleogene climate is poorly resolved. Our results demonstrate that pCO2 ranged between 1000 to 1500 parts per million by volume in the middle to late Eocene, then decreased in several steps during the Oligocene, and reached modern levels by the latest Oligocene. The fall in pCO2 likely allowed for a critical expansion of ice sheets on Antarctica and promoted conditions that forced the onset of terrestrial C4 photosynthesis."
Thus, it indicates the fall in pCO2 from 1500 ppm to modern levels (240 ppm) likely allowed for a critical expansion of the ice sheet of Antarctica, which is the effect one would expect falling co2 levels to have.
Concerning Paleogene: "Detailed investigations indicate that periods of rapid climate change often culminated in brief transient climates, with more extreme conditions than subsequent long term climates. Two examples of such events have been identified in the Paleogene; the first in latest Paleocene time in the middle of a warming trend that began several million years earlier: the second in earliest Oligocene time near the end of a Middle Eocene to Late Oligocene global cooling trend.
(cont.)
Superimposed on the earlier event was a sudden and extreme warming of both high latitude sea surface and deep ocean waters. Imbedded in the latter transition was an abrupt decline in high latitude temperatures and the brief appearance of a full size continental ice-sheet on Antarctica. In both cases the climate extremes were not stable, lasting for less than a few hundred thousand years, indicating a temporary or transient climate state. Geochemical and sedimentological evidence suggest that both Paleogene climate events were accompanied by reorganizations in ocean circulation, and major perturbations in marine productivity and the global carbon cycle. ..........It has been suggested that sudden changes in climate and/or ocean circulation might occur as a result of gradual forcing as certain physical thresholds are exceeded. We investigate the possibility that sudden reorganizations in ocean and/or atmosphere circulation during these abrupt transitions generated short-term positive feedbacks that briefly sustained these transient climatic states. "
http://www.jstor.org/pss/30081147
Regarding 500 million years ago. It is going way back! Three hundred million years ago there was only a single supercontinen callled Pangaea. Several hundred million years ago plants and fungi started growing at the edges of water. "The most severe extinction event to date took place 250 Ma, at the boundary of the Permian and Triassic periods; 95% of life on Earth died out, possibly due to the Siberian Traps volcanic event."
The huge supercontinent Pangaea did not break apart until 180 Ma, when it broke up into Laurasia and Gondwana. Then 65 million years ago the large comet stuck the earth in the Yucatan penisula killing off the rest of the dinosaurs.
According to another study: "Since 65 million years ago (Ma), Earth's climate has undergone a significant and complex evolution, the finer details of which are now coming to light through investigations of deep-sea sediment cores. This evolution includes gradual trends of warming and cooling driven by tectonic processes on time scales of 105 to 107 years, rhythmic or periodic cycles driven by orbital processes with 104- to 106-year cyclicity, and rare rapid aberrant shifts and extreme climate transients with durations of 103 to 105 years."
http://www.sciencemag.org/cgi/content/abstract/292/5517/686
I found a great pictoral reconstruction of past changes in landmasses due to continental shift, climate, and sea level here:
http://www.scotese.com/climate.htm
http://www.scotese.com/earth.htm
Fascinating stuff. Easy to forget that the earth of the dinosaurs was completely different.
"A new model has been constructed for calculating the level of atmospheric CO2 during the past 570 million years..... The model results indicate that CO2 levels were high during the Mesozoic and early Paleozoic and low during the Permo-Carboniferous and late Cenozoic. These results correspond to independently deduced Phanerozoic paleoclimates and support the notion that the atmospheric CO2 greenhouse mechanism is a major control on climate over very long time scales."
http://www.sciencemag.org/cgi/content/abstract/sci;249/4975/1382
Quantitative estimates of increased heat transfer by atmospheric H2O vapor during the Albian (112 million years ago to 99 million years ago) greenhouse warming suggest that the intensified hydrologic cycle played a greater role in warming high latitudes than at present and thus represents a viable alternative to oceanic heat transport.
http://geology.gsapubs.org/content/32/12/1049.abstract
Lowering of Co2 cooled the atmosphere during the Cretaceous period, 145 to 65 million years ago.
A low concentration of the greenhouse gas carbon dioxide in the Maastrichtian atmosphere (relative to concentrations in the earlier Cretaceous) is consistent with palaeotemperature information from terrestrial plant and marine fossils, which suggest that the global climate cooled toward the end of the Cretaceous Period.
http://jgs.lyellcollection.org/cgi/content/abstract/152/1/1
That is about all I have for now!
Interesting. This will take time to read and digest.
I've got lots of examples covering the Americas. Would you like me to cite some?
No, let's take a break.
good. my daughter is crook and I won't have time to look up papers until tomorrow. Until then.
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