Alaska is on the forefront of global focus in man-made climate change, because effects of it are quite marked and more rapid in the Arctic and sub-arctic latitudes (55N-90N). Particularly from Central Siberia, east through Alaska, Yukon and the Northwest territories, almost to Nunavut. These areas have seen the greatest climatic instability caused by the increase in summer and winter temperatures; melting of permafrost (which releases yet more carbon dioxide and methane, positive feedbacks), earlier springs, increased summer wildfire acreages (another positive feedback mechanism, releasing vast amounts of CO2 from the burned vegetation and soil) some years, and floods in others.
Ned Rozell is a science writer for the Geophysical Institute, at the University of Alaska, Fairbanks. Many researchers on the global forefront of climate change, also work there, some of whom I've had the honor to work and consult with about my thesis research project. Ned writes articles about all aspects of science, which you can read about in http://www.gi.alaska.edu/ScienceForum. It has articles archived back for many years, about alot of interesting subjects. He also writes regularly for Alaska Magazine, and has written several interesting books. http://www.amazon.com/Alaska-Tracks-Footprints-Country-Ambler/dp/1438232233/ref=sr_1_1?ie=UTF8&s=books&qid=1227654610&sr=1-1
Ned is also one of the best cross-country skiers in Fairbanks, a subject of great interest to the Alaska Progressive Review, and an inspiration. Because that wonderful form of exercise that enables one to use the whole body to propel it vast distances across the 6-7 month frozen landscape comes from our favorite Progressive nations of Norway, Sweden, and Finland. Socially-evolved and focused democracies. Ned's article describes the record-breaking low Arctic Ocean ice cover extent that occurred in summer, 2007.
After this article, we'll provide a current update of the Arctic Ice state, in 2008, along with a little discussion of the 4th U.N. International Panel on Climate Change (IPCC) report, the state of the science analysis of the past/current climate, and projected future climate based on expected emissions scenarios.
Alaska Science Forum December 12, 2007
Northern sea ice takes a big hit in 2007
Article #1885
by Ned Rozell
This column is provided as a public service by the Geophysical Institute, University of Alaska Fairbanks, in cooperation with the UAF research community. Ned Rozell is a science writer at the institute.
SAN FRANCISCO—For the past few years, vanishing northern sea ice has been a theme of many talks and posters here at the fall meeting of the American Geophysical Union, which draws about 15,000 scientists to the Moscone Center during the weeklong conference. At a press conference here on Wednesday, Dec. 12, 2007, scientists revealed that the ice on top of the northernmost ocean took a punch in the summer of 2007 that might be a knockout blow.
In 1980, the dense ice that floats on the Arctic Ocean like a large, moving jigsaw puzzle took up about the same area as the entire Lower 48 states; in September 2007, it was about as big as the U.S. east of the Mississippi River, said Don Perovich of the U.S. Army Cold Regions Research and Engineering Laboratory in New Hampshire. The ice loss in 2007, 23 percent greater than the previous record in 2005, has some scientists here predicting that the northern sea ice will vanish in summer as soon as five years from now. Perovich agreed that one of the greatest environmental changes people have ever seen might be close at hand.
Sea Ice off Gambell, Alaska. Photo by Ned Rozelle
“I used to say that sometime in my children’s lifetimes (sea ice covering the Arctic Ocean would disappear for half the year), but now I might see it,” said Perovich, who is in his 50s. John Walsh of the International Arctic Research Center in Fairbanks was, along with Perovich, one of four scientists facing reporters from all over the world on Wednesday morning. Walsh spoke of how warmer water from the Atlantic has been entering the Arctic Ocean. “We’re really moving into record territory in the last four or five years,” Walsh said, citing the work of IARC’s Igor Polyakov, who coordinates an annual scientific cruise in the Arctic Ocean. While surprisingly warm water from the Atlantic is entering the Arctic Ocean—which probably adds to the loss of sea ice by melting it from beneath—unusually warm water from the Pacific is also invading the Arctic Ocean through the Bering Strait, said Mike Steele of the University of Washington. “In 2007, north of Alaska and eastern Siberia, the Arctic Ocean was 3.5 degrees Celsius warmer than the historical average and 1.5 degrees warmer than the historical maximum,” Steele said, adding that waters off Alaska were especially warm. “The Bering Strait and Chukchi Sea are warming most.”
Because ice reflects about 85 percent of the sun’s radiation and open water only reflects 7 percent, 2007’s low ice led to the ocean absorbing much more of the sun’s heat. Perovich calculated that the Arctic Ocean in September 2007 absorbed 300 percent more solar energy than it did in 1980. He said that the sun was the real culprit in the loss of sea ice this year, and that the warm pulses of Atlantic and Pacific water also eroded the ice pack.
Perovich and his colleagues monitored a piece of sea ice off Alaska’s coast on the Beaufort Sea this year, finding it was almost 11 feet thick in June but shrunk to less than two feet thick by September. Ice seems to be at least three feet thinner than normal almost everywhere scientists have measured it.
“That missing meter of ice means the ice is more vulnerable,” Steele said.
The loss of ice in the summer will happen soon unless things change drastically, the scientists said. “As you go further down this path, it’s harder to get back,” Perovich said. “It’s the fourth quarter now, and we’re down two touchdowns.”
For all the dire predictions that would spell the doom of the polar bear and other creatures that depend on sea ice, the sea ice could still bounce back, Steele said.“Ice grows quickly when the air is really cold,” he said. “A recipe to bring the ice back is a few cold winters in a row.”
Smoke from the Boundary Fire, along the Chatanika River, 40 miles northeast of Fairbanks, June, 2004, 10 days before it became a conflagration, and was pushed toward Fairbanks. Photo by Michael Richmond.
The Boundary Fire, 500,000 acres and one month later, July, 2004. Photo by Dave Dallison. Fire Behavior analyst, Rocky Mountain Interagency Type I Suppression Team.
ARCTIC SEA ICE UPDATE 2008
Arctic sea ice extent during the 2008 melt season dropped to the second-lowest level since satellite measurements began in 1979, reaching the lowest point in its annual cycle of melt and growth on September 14, 2008. Average sea ice extent over the month of September, a standard measure in the scientific study of Arctic sea ice, was 4.67 million square kilometers (1.80 million square miles) (Figure 1). The record monthly low, set in 2007, was 4.28 million square kilometers (1.65 million square miles); the now-third-lowest monthly value, set in 2005, was 5.57 million square kilometers (2.15 million square miles).
The 2008 season strongly reinforces the thirty-year downward trend in Arctic ice extent. The 2008 September low was 34% below the long-term average from 1979 to 2000 and only 9% greater than the 2007 record (Figure 2). Because the 2008 low was so far below the September average, the negative trend in September extent has been pulled downward, from –10.7 % per decade to –11.7 % per decade (Figure 3).
NSIDC Senior Scientist Mark Serreze said, “When you look at the sharp decline that we’ve seen over the past thirty years, a ‘recovery’ from lowest to second lowest is no recovery at all. Both within and beyond the Arctic, the implications of the decline are enormous.”
That was the latest from the National Sea and Ice Data Center, in Boulder, CO
"Our supporters fund data management and scientific research at the project level. For example, the National Aeronautics and Space Administration (NASA) supports the NSIDC Distributed Active Archive Center (DAAC) and funds the production and distribution of remote-sensing data sets. The National Science Foundation (NSF) provides data management for scientists doing polar research. The National Oceanic and Atmospheric Administration (NOAA) provides support for management of NOAA data sets at NSIDC and has funded many of the center's data-rescue activities. NASA, NOAA and NSF, as well as additional sources of funding, support NSIDC scientists and outreach activities through competitive grants and contracts NSIDC is part of the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado at Boulder. The University and CIRES provide a collaborative environment and support for our research."
This institude, funded and staffed by U.S. government agencies and universities, is THE source for accurate, state of the science ice data and trends.
So what are the effects and implications of reduced Arctic sea ice? Less summer ice allows a greater expanse of the Arctic ocean to absorb solar radiation. Water with it's much greater heat capacity than air, absorbs a vast amount more of heat, which is then transported around the basin, helping melt more ice, etc... Which is another positive feedback. This then causes more warming, longer, warmer Arctic summers with greater fire acreages, increased thunderstorm activity (because of a deeper troposphere in the warm season) to start the fires, warmer springs that end earlier, etc..
It has been found that in the shallower depths of the Arctic Ocean basin, along the continental shelves, are vast deposits of frozen methane. Methane that if allowed to melt by warmer water, would be released into the atmosphere, and could, if unchecked, lead to rapid and lethal global warming of average temperatures to as high as 140F! Temperatures which were reached 200+ million years ago, during the "End-Permian Exctinction", in which 95 percent of the species in the fossil record, disappeared. http://www.amazon.com/When-Life-Nearly-Died-Extinction/dp/050005116X
Methane is over 20 times more efficient in warming the atmosphere than carbon dioxide, and there are already disturbing reports of higher atmospheric methane levels in the Arctic ocean north of Siberia.
http://www.independent.co.uk/environment/climate-change/exclusive-the-methane-time-bomb-938932.html
The End-Permian extinction is thought to have been triggered by a global average temperature rise of 10C, caused by massive volcanism in Siberia, which released vast amounts of CO2, causing it. The 10C warming caused the frozen Arctic methane deposits to melt, in a giant methane "burp" which triggered the catastrophic runaway warming, causing the 95 percent species mortality. This 10C warming is on the very upper-end of climate change modeling scenarios results for the planet 60-80 years hence. A disturbing picture to be sure.
Climate-change sceptics have tried to sow confusion and doubt about the veracity and scientific robustness of the latest research. Many of these sceptics have ties to the fossil-fuel industries, which is not surprising. However, if we are to accept that science describes aspects of our physical reality, and use the technology that it has brought, electricity, modern transportation, medicine, etc... then we cannot ignore these reports. To do so would be to deny that science as we know it is valid, and would be very hypocritical. The U.N. International Panel for Climate Change (IPCC), a global consortium of climate-change researchers investigating all aspects of the Earth's climate system, have issued four assessment reports, the latest in 2007. This link is a good summary of the findings from it. http://en.wikipedia.org/wiki/IPCC_Fourth_Assessment_Report
If you want to read the actual report, here is a link to a .pdf version of it:
http://www.ipcc.ch/pdf/assessment-report/ar4/syr/ar4_syr.pdf
There really isn't any doubt among the scientific community about human-caused global warming, the questions now are, how much warming will occur, what will the effects be on regional scales, and what can be done to help mitigate, if possible, these changes. The movie that ex-Vice President Al Gore produced, "An Inconvenient Truth" was also a good depiction of the problems we face. Every researcher I've talked with agreed that the movie was accurate and reflected the state of current knowledge about the problem. There are still alot of unknowns concerning feedbacks and interaction processes between the atmosphere, oceans, cryosphere (ice cover), and biosphere, which are the subject of research by thousands of scientists, world-wide. What is most disturbing, is that the pace of changes we have seen, for instance, in retreat of Arctic ice cover, has been far faster than climate change modeling predicted. James Hansen, a climate change researcher who works for NASA, has stated that a 2-3C increase in global temperatures caused ice sheet melting in Greenland and the southern edge of Antarctica 3.5 million years ago which raised sea levels 25 meters in a very short time, a few decades, not centuries. That the response of the climate system was non-linear, with a "tipping point", beyond which there was no way to stop it. The current atmospheric CO2 concentration of 385 parts per million (ppm), is increasing 3-4 ppm annually and Hansen has estimated that a concentration approaching 450 ppm, which is now less than 20 years away, would bring the tipping-point warming of 2-3C, and lead to the rapid ice-sheet melting and sea level rise. Given the fact that changes are already occurring faster than models have suggested, it would seem prudent that a concentrated global fast-track effort needs to be done, to prevent catastrophic changes. http://www.commondreams.org/view/2008/11/25-1 . This latest article, by George Monbiot, a British environmental writer, for their Guardian newspaper, is a good resource, and is heartily endorsed by the A.P.R.
In the face of this mounting threat of catastrophic warming and climatic disruption, what can and should individuals do, to try and prevent its occurrence? That will be the subject of next week's writing, in your Alaska Progressive Review.
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