Antarctica Melting FASTER!, page 4
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reply posted on 23-11-2009 @ 02:16 PM by ProfEmeritus
One of the most objective, and reasoned discussions on this topic, in my humble opinion is the research published by the British Antarctic Society:

www.antarctica.ac.uk...


First, they explain why the Antarctic is important:
Climate change - causes and effects

December 2007

Why should we study Antarctic climate?
The Antarctic region is an important regulator of global climate. The Southern Ocean is a significant sink for both heat and carbon dioxide, acting as a buffer against human-induced climate change. The sea ice that forms around the continent each winter controls the exchange of energy between the Sun and the Earth, and its partition between atmosphere and ocean. As sea ice forms, brine rejected from the ice increases the density of the upper ocean. These waters then sink and form the deep ocean currents that carry heat around the globe.

Changes in global climate can have impacts on the Antarctic environment. The Southern Ocean supports a unique ecosystem that is well adapted to present climate conditions. Changes in ocean temperatures, currents and sea ice will impact on this ecosystem, possibly changing the ocean's capacity to absorb carbon dioxide. Warming of the atmosphere and ocean around Antarctica may lead to increased loss of mass from the Antarctic ice sheets and hence a rise in global sea level. In order to make soundly-based predictions of how the global environment may change over the coming decades and centuries, we need to understand the role played by the Antarctic in the Earth system.


Next, they take a reasoned look at the last 50 years:


How has Antarctic climate varied over the past 50 years?
Few continuous observations of Antarctic climate are available before the International Geophysical Year of 1957-58. Since this time, surface temperatures have remained fairly stable over much of Antarctica, although individual station records show a high level of year-to-year variability, which could mask any underlying long term-trend. The majority of stations in East Antarctica, including the two long-term records from the high plateau of East Antarctica (South Pole and Vostok) show no statistically-significant warming or cooling trends1. By contrast, large and statistically-significant warming trends are seen at stations in the Antarctic Peninsula. Over the past 50 years, the west coast of the Peninsula has been one of the most rapidly-warming parts of the planet. Here, annual mean temperatures have risen by nearly 3°C, with the largest warming occurring in the winter season1,2,3. This is approximately 10 times the mean rate of global warming, as reported by the Intergovernmental Panel on Climate Change (IPCC). The east coast of the Peninsula has warmed more slowly and here the largest warming has taken place in summer and autumn3.

Significant warming has also been observed in the Southern Ocean. Upper ocean temperatures to the west of the Antarctic Peninsula have increased by over 1°C since 19554. Within the circumpolar Southern Ocean, it is now well-established that the waters of the Antarctic Circumpolar Current (ACC) are warming more rapidly than the global ocean as a whole. A comparison of temperature measurements from the 1990s with data from earlier decades shows a large-scale warming of around 0.2°C in the ACC waters at around 700-1100 m depth21.

Analysis of weather balloon data collected over the past 30 years has shown that the Antarctic atmosphere has warmed below 8 km and cooled above this height. This pattern of warming in the troposphere and cooling in the stratosphere is seen globally and is the expected signature of increases in greenhouse gases, such as carbon dioxide. However, the 30-year warming at 5 km over the Antarctic during winter (0.75°C) is over three times the average rate of warming at this level for the globe as a whole5.

Reliable year-round measurements of Antarctic sea ice extent are only available from the 1970s, when satellite observations first became available. Unlike in the Arctic, where there has been a significant decline in observed sea ice extent over this period, there has been a small but statistically-significant increase in the overall extent of Antarctic sea ice. However, there are strong geographical variations at a regional scale. Sea ice cover has declined substantially in the seas to the west of the Antarctic Peninsula while it has increased in other parts of the Antarctic6.

Subtle but important changes have occurred in the atmospheric circulation around Antarctica. Since the early 1960s, atmospheric pressure has dropped over Antarctica and risen in the mid-latitudes of the Southern Hemisphere, a pattern of variability known as the Southern Hemisphere Annular Mode (SAM)7. These changes have resulted in a strengthening of the westerly winds that blow over the Southern Ocean around Antarctica. Stronger westerlies will impact on ocean currents, upwelling and mixing, but the consequences of such changes have yet to be fully understood.



They then discuss how recent environmental changes have affected the Antarctic:



How has recent climate change impacted on the Antarctic environment?
Recent climate change has driven significant changes in the physical and living environment of the Antarctic. Environmental change is most apparent in the Antarctic Peninsula, where climate change has been largest. Adélie penguins, a species well adapted to sea ice conditions, have declined in numbers and been replaced by open-water species such as chinstrap penguins8. Melting of perennial snow and ice covers has resulted in increased colonisation by plants9. A long-term decline in the abundance of Antarctic krill in the SW Atlantic sector of the southern ocean may be associated with reduced sea ice cover10.

Large changes have occurred in the ice cover of the Peninsula. Many glaciers have retreated11 and around 10 ice shelves that formerly fringed the Peninsula have been observed to retreat in recent years12 and some have collapsed completely. Furthermore, 87% of glaciers along the west coast of the AP have retreated in the last 50 years, and in the last 12 years most have accelerated. The Antarctic Peninsula is contributing to sea-level rise, at about the same rate as Alaska Glaciers.

Analysis of global measurements of atmospheric CO2 indicates that the Southern Ocean carbon sink has weakened significantly since 1981. This reduction in the capacity of the ocean to absorb CO2 has been attributed to increased upwelling of carbon-rich waters associated with strengthening of the westerly winds19. Although future changes in the ability of the Southern Ocean to sequester CO2 are not completely known, this will be a key factor that helps shape global climate.


Continued on my next post.


reply posted on 23-11-2009 @ 02:17 PM by ProfEmeritus
They then discuss human activity and its possible affects:


Has human activity caused the recent changes?
Climate can vary as a result of changes in forcing factors that affect the way energy is exchanged between the sun, the earth and space. These forcings can be of natural origin (e.g. volcanic dust in the atmosphere, variations in solar output and variations in the Earth's orbit about the sun) or a result of human activity (e.g. increases in "greenhouse" gases such as carbon dioxide). Additionally, complex interactions between atmosphere, oceans and sea ice can cause climate variability, particularly on a regional scale, over a timescale of years to decades. Attributing observed changes in climate to particular changes in forcing (or to natural variability) is a difficult process that can only be accomplished by bringing together reliable observations of past and present climate with the results of experiments carried out with sophisticated models of the climate system. Attribution of Antarctic climate change is particularly difficult because of the relatively small number of instrumental climate records available from this region and the short length of the records.

As part of the work undertaken for the Fourth Assessment Report of the IPCC13, about 20 different climate models were run with historical changes to natural and anthropogenic forcing factors to simulate the climate of the 20th century. The simulated changes in Antarctic surface temperatures over the second half of the 20th century vary greatly from model to model with no single model reproducing exactly the observed pattern of change. However, when results from all models are averaged, the resulting pattern of change bears some resemblance to that observed, with greatest warming in the Peninsula region and little change elsewhere20. This result suggests that some of the observed change may have an anthropogenic origin, but the lack of a clear and consistent response to changed forcing between models also suggests that much of the observed change in temperatures may be due to natural variability. The IPCC model experiments fail to reproduce some of the observed features, notably the rapid warming of the lower atmosphere. These differences between modelled and observed changes could be used to argue against attributing change to anthropogenic forcing but some caution is called for as the models used may not adequately represent all of the complex processes that determine temperatures in the polar regions.

Most of the IPCC model experiments do simulate the observed strengthening of the circumpolar westerly winds, suggesting that this phenomenon is a robust response to changed climate forcing. Further experiments have indicated that changes in anthropogenic forcings, particularly stratospheric ozone depletion and increases in greenhouse gases, have made the largest contribution to the strengthening of the westerlies14,15. Recent climate observations show that changes in the strength of the westerlies strongly influence temperature variations on the east coast of the Antarctic Peninsula16. Taken together, these two results suggest that a significant fraction of the recent observed changes in climate in this part of the Antarctic can be attributed to human activity with a reasonable degree of certainty. Further support for this view comes from analysis of marine sediment records which enable us to examine how the extent of Antarctic Peninsula ice shelves has varied over time. While some of the smaller ice shelves in this region have periodically grown and decayed over the past 10000 years17, the Larsen-B ice shelf appears to have been stable throughout this period until it collapsed suddenly in March 200218. This suggests that recent warm temperatures are exceptional within the context of the last 10000 years, making it unlikely that they can be explained by natural variability alone.

Many of the theories that seek to explain the circumpolar warming of the ACC also have the strengthening of the westerly winds as their root cause. Whilst there is not yet a clear consensus on which are the mechanisms that are most important, there is increasing evidence that a significant part of this change is ultimately driven by human activities22.



Finally, their CONCLUSION:


What further changes can we expect over the next 100 years?
If we make assumptions about how greenhouse gas emissions are likely to change, we can use climate models to predict how Antarctic climate may respond over the coming century. Models predict a warming of a few degrees celsius over much of continental Antarctica. However, as mean temperatures over most of the continent are well below freezing, even this warming will not greatly increase loss of ice from the continent through melting. Indeed, increases in snowfall resulting from a warmer atmosphere (which can hold more water vapour) may actually thicken the Antarctic ice sheets.

Warming is also predicted in and over the oceans surrounding Antarctica. As a result, sea ice cover may decline by around 25% (although there are considerable uncertainties associated with this prediction). Where warmer ocean waters come into contact with the continental ice sheets, loss of ice from the continent will be accelerated.

Although stratospheric ozone levels are predicted to recover as a result of implementation of the Montreal Protocol (and its subsequent revisions), model predictions indicate that the circumpolar westerly winds will continue to strengthen as the effects of increasing greenhouse gases outweigh those of reducing ozone. Further change associated with strengthening winds may be expected in the Southern Ocean environment, including, possibly, further reduction in the strength of the Southern Ocean carbon sink.



reply posted on 23-11-2009 @ 02:29 PM by VonDoomen
reply to post by whattheh


Well I think the main issue here is whether its anthropocentric warming, or the earth/sun/solarsystem causing the warming.

The truth is, parts of the arctic are melting, as we see from all these melting glaciers.


reply posted on 23-11-2009 @ 02:41 PM by ProfEmeritus
reply to post by Equinox99




Could this be another propaganda to to pay money to carbon credit taxes?


You think?

rense.com...


reply posted on 23-11-2009 @ 02:42 PM by TSZodiac
reply to post by loner007


Okay - here we go again, you people see a headline - you say "see, told you so" and start bad mouthing anyone who DARES to disagree. Well, did any of you "Gore-ites" even BOTHER to actually READ the article that was posted above? Did you see the part about the study's margin of error? Here, allow me to quote it for you..."the Margin of Error (in the study), they cautioned, is almost as much as the estimate (of the loss of mass)".
SO - here we have a SHORT TERM (7 year study) where the margin of error is almost the same number as the alledged loss of mass. So basically there could have been NO LOSS AT ALL - my guess is that (since the snow and ice data center at the University of Colorado - which actually sends scientists to the Antarctic to physically check ice levels as well as using satellites - says that Antarctic Ice is WELL ABOVE the average for the years 2001-2008) we are looking at FAULTY SCIENCE (hence the ENORMOUS margin of error). My next guess is that since the hoax that is "Man made Global Warming" is the brainchild of the POLITICAL arena and not of the SCIENTIFIC arena, this so called study was rushed out to the public to counter the damage that was done by the hacking of the Hadley Institute. The emails/documents that were captured from Hadley should be the basis for charges to be brought against the people at Hadley and elsewhere that are being paid to skew the science to fit the model (these aren't MY words - they are words taken from the emails).


reply posted on 23-11-2009 @ 03:06 PM by Psychonaughty
reply to post by atlasastro


Change is all that it is, there is not an ending only change.


reply posted on 23-11-2009 @ 03:40 PM by ProfEmeritus
reply to post by whatshenneping




The University of East Anglia's Hadley Climatic Research Centre appears to have suffered a security breach earlier today, when an unknown hacker apparently downloaded 1079 e-mails and 72 documents of various types and published them to an anonymous FTP server. These files appear to contain highly sensitive information that, if genuine, could prove extremely embarrassing to the authors of the e-mails involved. Those authors include some of the most celebrated names among proponents of the theory.


Yes, in fact, here are some specifics:

www.abc.net.au...


A few days ago computer hackers stole private emails and research documents from the University of East Anglia.

In one of the leaked emails, respected US climatologist Kevin Trenberth admits that scientists cannot account for the lack of global warming to date.

"The fact is that we can't account for the lack of warming at the moment and it is a travesty that we can't... Our observing system is inadequate," the email says.



bishophill.squarespace.com...


General reaction seems to be that the CRUgate emails are genuine, but with the caveat that there could be some less reliable stuff slipped in.

In the circumstances, here are some summaries of the CRUgate files. I'll update these as and when I can. The refs are the email number.

* Phil Jones writes to University of Hull to try to stop sceptic Sonia Boehmer Christiansen using her Hull affiliation. Graham F Haughton of Hull University says its easier to push greenery there now SB-C has retired.(1256765544)
* Michael Mann discusses how to destroy a journal that has published sceptic papers.(1047388489)
* Tim Osborn discusses how data are truncated to stop an apparent cooling trend showing up in the results (0939154709). Analysis of impact here. Wow!
* Phil Jones describes the death of sceptic, John Daly, as "cheering news".(1075403821)
* Phil Jones encourages colleagues to delete information subject to FoI request.(1212063122)
* Phil Jones says he has use Mann's "Nature trick of adding in the real temps to each series"...to hide the decline". Real Climate says "hiding" was an unfortunate turn of phrase.(0942777075)
* Letter to The Times from climate scientists was drafted with the help of Greenpeace.(0872202064)
* Mann thinks he will contact BBC's Richard Black to find out why another BBC journalist was allowed to publish a vaguely sceptical article.(1255352257)
* Kevin Trenberth says they can't account for the lack of recent warming and that it is a travesty that they can't.(1255352257)
* Tom Wigley says that Lindzen and Choi's paper is crap.(1257532857)
* Tom Wigley says that von Storch is partly to blame for sceptic papers getting published at Climate Research. Says he encourages the publication of crap science. Says they should tell publisher that the journal is being used for misinformation. Says that whether this is true or not doesn't matter. Says they need to get editorial board to resign. Says they need to get rid of von Storch too. (1051190249)
* Ben Santer says (presumably jokingly!) he's "tempted, very tempted, to beat the crap" out of sceptic Pat Michaels. (1255100876)
* Mann tells Jones that it would be nice to '"contain" the putative Medieval Warm Period'. (1054736277)
* Tom Wigley tells Jones that the land warming since 1980 has been twice the ocean warming and that this might be used by sceptics as evidence for urban heat islands.(1257546975)
* Tom Wigley say that Keith Briffa has got himself into a mess over the Yamal chronology (although also says it's insignificant. Wonders how Briffa explains McIntyre's sensitivity test on Yamal and how he explains the use of a less-well replicated chronology over a better one. Wonders if he can. Says data withholding issue is hot potato, since many "good" scientists condemn it.(1254756944)
* Briffa is funding Russian dendro Shiyatov, who asks him to send money to personal bank account so as to avoid tax, thereby retaining money for research.(0826209667)
* Kevin Trenberth says climatologists are nowhere near knowing where the energy goes or what the effect of clouds is. Says nowhere balancing the energy budget. Geoengineering is not possible.(1255523796)
* Mann discusses tactics for screening and delaying postings at Real Climate.(1139521913)
* Tom Wigley discusses how to deal with the advent of FoI law in UK. Jones says use IPR argument to hold onto code. Says data is covered by agreements with outsiders and that CRU will be "hiding behind them".(1106338806)
* Overpeck has no recollection of saying that he wanted to "get rid of the Medieval Warm Period". Thinks he may have been quoted out of context.(1206628118)
* Mann launches RealClimate to the scientific community.(1102687002)
* Santer complaining about FoI requests from McIntyre. Says he expects support of Lawrence Livermore Lab management. Jones says that once support staff at CRU realised the kind of people the scientists were dealing with they became very supportive. Says the VC [vice chancellor] knows what is going on (in one case).(1228330629)
* Rob Wilson concerned about upsetting Mann in a manuscript. Says he needs to word things diplomatically.(1140554230)
* Briffa says he is sick to death of Mann claiming his reconstruction is tropical because it has a few poorly temp sensitive tropical proxies. Says he should regress these against something else like the "increasing trend of self-opinionated verbiage" he produces. Ed Cook agrees with problems.(1024334440)
* Overpeck tells Team to write emails as if they would be made public. Discussion of what to do with McIntyre finding an error in Kaufman paper. Kaufman's admits error and wants to correct. Appears interested in Climate Audit findings.(1252164302)
* Jones calls Pielke Snr a prat.(1233249393)
* Santer says he will no longer publish in Royal Met Soc journals if they enforce intermediate data being made available. Jones has complained to head of Royal Met Soc about new editor of Weather [why?data?] and has threatened to resign from RMS.(1237496573)
* Reaction to McIntyre's 2005 paper in GRL. Mann has challenged GRL editor-in-chief over the publication. Mann is concerned about the connections of the paper's editor James Saiers with U Virginia [does he mean Pat Michaels?]. Tom Wigley says that if Saiers is a sceptic they should go through official GRL channels to get him ousted. (1106322460) [Note to readers - Saiers was subsequently ousted]
* Later on Mann refers to the leak at GRL being plugged.(1132094873)
* Jones says he's found a way around releasing AR4 review comments to David Holland.(1210367056)
* Wigley says Keenan's fraud accusation against Wang is correct. (1188557698)
* Jones calls for Wahl and Ammann to try to change the received date on their alleged refutation of McIntyre [presumably so it can get into AR4](1189722851)
* Mann tells Jones that he is on board and that they are working towards a common goal.(0926010576)
* Mann sends calibration residuals for MBH99 to Osborn. Says they are pretty red, and that they shouldn't be passed on to others, this being the kind of dirty laundry they don't want in the hands of those who might distort it.(1059664704)
* Prior to AR3 Briffa talks of pressure to produce a tidy picture of "apparent unprecedented warming in a thousand years or more in the proxy data". [This appears to be the politics leading the science] Briffa says it was just as warm a thousand years ago.(0938018124)
* Jones says that UK climate organisations are coordinating themselves to resist FoI. They got advice from the Information Commissioner [!](1219239172)
* Mann tells Revkin that McIntyre is not to be trusted.(1254259645)
* Revkin quotes von Storch as saying it is time to toss the Hockey Stick . This back in 2004.(1096382684)
* Funkhouser says he's pulled every trick up his sleeve to milk his Kyrgistan series. Doesn't think it's productive to juggle the chronology statistics any more than he has.(0843161829)
* Wigley discusses fixing an issue with sea surface temperatures in the context of making the results look both warmer but still plausible. (1254108338)
* Jones says he and Kevin will keep some papers out of the next IPCC report.(1089318616)
* Tom Wigley tells Mann that a figure Schmidt put together to refute Monckton is deceptive and that the match it shows of instrumental to model predictions is a fluke. Says there have been a number of dishonest presentations of model output by authors and IPCC.(1255553034)
* Grant Foster putting together a critical comment on a sceptic paper. Asks for help for names of possible reviewers. Jones replies with a list of people, telling Foster they know what to say about the paper and the comment without any prompting.(1249503274)
* David Parker discussing the possibility of changing the reference period for global temperature index. Thinks this shouldn't be done because it confuses people and because it will make things look less warm.(1105019698)
* Briffa discusses an sceptic article review with Ed Cook. Says that confidentially he needs to put together a case to reject it (1054756929)
* Ben Santer, referring to McIntyre says he hopes Mr "I'm not entirely there in the head" will not be at the AGU.(1233249393)
* Jones tells Mann that he is sending station data. Says that if McIntyre requests it under FoI he will delete it rather than hand it over. Says he will hide behind data protection laws. Says Rutherford screwed up big time by creating an FTP directory for Osborn. Says Wigley worried he will have to release his model code. Also discuss AR4 draft. Mann says paleoclimate chapter will be contentious but that the author team has the right personalities to deal with sceptics.(1107454306)
*


Update on November 22, 2009 by Registered CommenterBishop Hill

Updated to add links to the online database of the emails at Elegant Chaos.
Update on November 22, 2009 by Registered CommenterBishop Hill

)Here's more:

* Phil Jones having problems with explaining issues over the Lamb image of global temps in the early IPCC reports. Says it shouldn't be discussed openly at Real Climate. Says better left buried.(1168356704)
* Phil Jones emails Steve [Schneider], editor of Climatic Change [plus others, editorial board of the journal?], telling him he shouldn't accede to McIntyre's request for Mann's computer code. In later email to Mann ("For your eyes only, delete after reading") Jones says he told Jones separately [presumably meaning without saying to the rest of the board] that he should seek advice elsewhere and also consult the publisher and take legal advice.(1074277559)
* Briffa says he tried hard to balance the needs of the IPCC and science, which were not always the same.(1177890796)
* An anonymous source says that robustness problems with the Hockey Stick are known to anyone who understands his methodology. The source says that there will be a lot of noise over McIntyre's 2003 paper and that knowing Mann'svery thin skin he will react strongly, unless he has learned from the past.(1067194064)
* Giorgio Filippo (University of Trieste) says that IPCC is not an assessment of published science but about production of results. Says there are very few rules and anything goes. Thinks this will undermine IPCC credibility. Says everyone seems to think it's OK to do this.(0968705882)
* IPCC review editor John Mitchell says that the issue of why proxy data for recent decades is not shown (he says it's because they don't show warming) needs to be explained. [Note to readers, this was not done Let's say that the explanation was nuanced - it said that the divergence problem, as this issue is known, was restricted to a few areas]. Also says that Mann's short-centred PC analysis is wrong and that Mann's results are not statistically significant.(1150923423)



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