Search Results for Tag: Warming
Permafrost “tipping point” in less than 20 years?
I have been concerned about the effect of melting permafrost on the climate for quite some time, not least in the wake of encounters with scientists working in Greenland (this picture is Zackenberg, Greenland, 2009) and Alaska. Now research results published by the National Snow and Ice Data Centre (NSDIC) in Boulder, Colorado are indicating that there could be a “tipping point” or a “starting point”, as Professor Kevin Schaefer prefers to call it, in less than 20 years. That means a point when the vast areas of permafrost in Alaska, Canada, Siberia and parts of Europe go from being a “carbon sink” to a carbon source. The study indicates as much as two-thirds of the carbon frozen into the permafrost could be released.
There’s more info on the NSIDC website and on the ips news website, based on an interview with Prof. Schaefer. Not happy reading, but without big reductions in emissions, it will probably be impossible to prevent this. On top of that come the methane emissions, not included in the study. Methane is much more powerful than CO2 as a greenhouse gas.
DateFebruary 18, 2011 | 3:12 pm
On the trail of the truth about Greenland
Running for campus…
Let me recommend you a website and the book it’s based on.I’ve seen it here and it’s very impressive:Arctic Tipping Points
is the title, and it contains some beautiful and in some cases moving images relating to climate change and the Arctic. The editors are Carlos Duarte (quoted in earlier post) and Paul Wassmann (University of Tromsö.
(No tipping point for these swings)
I have been following the presentations dealing with the Greenland ice sheet closely. Sometimes it is a little frustrating when speakers hint at important results of studies which they cannot reveal fully ahead of publication. If you guys are trying to increase the suspense and arouse my interest in reports coming out in the next few months – you have succeeded. On the other hand, it seems a pity, with quite a few journalists sitting in the conference, that we can’t use the opportunity to pass on some interesting results. Unfortunate timing, it seems some of the reports were originally planned to have been ready. But let me sum up what I can here.
Peter Wadhams, Professor of Ocean Physics at the University of Cambridge introduced the strain of the conference dedicated to “ice-ocean-atmosphere interactions in the Arctic”. He refered to very large changes on the Greenland ice sheet, with very large areas of melt occurring in summer and a substantial net flux of fresh water into the sea every year. Now that is one of the key factors in measuring the changes. He told us the amount was almost the same as the total melt from mountain glaciers, suggesting this could be making a comparable contribution to global sea level rise as melt from all the rest of the glaciers in the world put together. He stressed the rate of melt on Greenland is accelerating and scientists just don’t know how the acceleration rate will continue.
Lars Otto Reiersen is the Executive Secretary for AMAP, the Arctic Monitoring and Assessment Programme. He reported on the SWiPA (Project) (Snow, Water, Ice and Permafrost in the Arctic), which is preparing a report to be presented to a meeting of Arctic ministers in May. (sigh!) Suffice it to say, he indicated that when it comes to the mass balance of the Greenland ice sheet, the updated figures will show even higher melt. All will be revealed in a few months, it seems. And it will not be cheery reading.
Late afternoon impression of Tromsö campus while the weather was still beautiful (some like it cold). It is thawing at the moment, but forecast to cool again soon.
DateJanuary 27, 2011 | 3:55 pm
Greenland ice sheet to melt at lower temperature than anticipated?
I am sitting in the opening session of the science section of the Arctic Frontiers conference gathering scientists and experts from around the world in the Norwegian Arctic town of Tromsö. Leading German climate scientist Stefan Rahmstorf of the Potsdam Institute for Climate Impact research has just quoted an as yet unpublished paper by colleagues, currently being reviewed, indicating that the temperature threshold for a melting of the Greenland ice sheet could be as low as 1.3 to 2.3 degrees C. The IPCC assessment assumes a temperature rise of 1.9 to 4.6 degrees C. as the critical threshold.
The Cancun agreement to limit warming to 2 degrees was based on IPCC figures. There is however an agreement on the need to review the scientific basis for the maximum temperature rise limit.
Given the huge significance of the Greenland ice sheet – a complete melting of the Greenland ice sheet could mean a rise in sea level of 7 metres- this would be a very significant new study, assuming it is reviewed positively. He expects it to be published in a month or two. Rahmstorf does not want to say any more, as it is not his paper and the authors are not present. But he is not the sort of scientist who quotes studies without careful consideration. He says he\’s glad the Cancun conference agreed to keep reviewing the science that provides the basis for setting the temperature limits.
DateJanuary 26, 2011 | 9:30 am
Arctic Science and Politics
It was a full house all day here in the world’s northernmost university.
The first two days are designated the “political” section, Wednesday to Friday will be the “science” section. Of course there has to be some overlap, with the scientific background for the politicians and the political considerations giving context to the scientists.
At lunchtime I talked to some scientists from North America and Europe attending the whole week. They seemed to have the feeling the political discussions were only skimming the surface. Some of them also said – and I’ve heard this a number of times before at conferences like this – it was a real pity the politicians didn’t stay around to engage with the scientists. There seems to be a consensus though that it is a good idea to bring scientists and the politicians who have the responsibility to decide on action taken based on scientific research – and to fund research – together more often.
US Rear Admiral Dave Titley had an interesting interpretation of the “tipping point” theme. “Melting sea ice in the Polar Ocean – a tipping point for US politics in the Arctic” was his presentation. He was stressing the Arctic is “tipping” into the mainstream, i.e. no longer a remote area, but one where shipping and oil and gas extraction would be on the increase from 2030 onwards, with a whole month ice-free every summer. He made no bones about the fact that the ice is melting fast and we need progress on a “polar code” and search-and-rescue procedures. He says it’s just a matter of luck that there has been no major cruise ship disaster so far, in what will remain dangerous waters.
In between times I talked to a Norwegian and two Russian “explorers”, who know all about that, the ones who took ships through the northern sea passages just last year. Things are really changing fast up here. That brings us back to the tipping points.
Spanish marine ecology professor Carlos Duarte was the “scientist amongst the politicians”. And he painted a worrying picture. 6 out of 14 “tipping elements” in the earth system, he says, are located in the Arctic. Let me close with a quick list of the dangerous factors he described: sea ice and albedo, the Greenland ice sheet, sea level rise, thermokarst and permaforost melting, increased freshwater runoff, methane hydrate release, pollutant release, ocean reversal to a CO2 source, boreal forest dieback and peat fires. While the Greenland ice cap melting and sea level increase are likely to be very long-term factors, the others could all be acting within decades, he says, and “tipping over” like dominos. He told me in an interview that he is really concerned with the paradox involved in exploiting even more fossil fuels which will further increase global warming and bring the “points of no return” closer, faster. He feels we are not far away from the “tipping point” represented by melting Arctic sea ice.He thinks the politicians have to abandon their reluctance to take unilateral steps and get moving.
DateJanuary 25, 2011 | 11:46 am
2010 ties for “warmest year on record”
NASA’s Goddard Institute for Space Studies (GISS) has released figures confirming that 2010 tied with 2005 for the warmest global surface temperatures ever recorded. According to the analysis, the next warmest years are 1998, 2002, 2003, 2006 and 2007.The GISS records go back to 1880.
“If the warming trend continues as is expected, if greenhouse gases continue to increase, the 2010 record will not stand for long”, says the Institute’s director James Hansen.
NASA says their temperature record is a close match with those of others, independently produced, including the UK’s
Met Office Hadley Centre
and the National Oceanic and Atmospheric Administration’s National Climatic Data Center.
Hansen says the records show a rise in temperature over the last ten years in spite of year-to-year fluctuations associated with the El Nino – La Nina cycle of tropical ocean remperature. There is also a possibility that the cold spell which had us diving for the snow shovels here in northern Europe could have been influenced by the decline of Arctic sea ice and linked to warming temperatures at more northern latitudes. The sea ice helps insulate the atmosphere from the ocean’s heat.
The GISS experts say winter weather patterns are “notoriusly chaotic”. Well, climate is certainly a complex business. But whatever way you look at it, it looks like we all have our work cut out for us to have any chance of halting the worrying upward trend in temperature.
DateJanuary 13, 2011 | 1:18 pm