Scientists expect that the Arctic will be fully ice-free during summer sometime during this century. Graph by: Dominiklenne.
Last year the Arctic, which is warming faster than anywhere else on Earth due to global climate change, experienced its warmest twelve months yet. According to recent data by NASA, average Arctic temperatures in 2011 were 2.28 degrees Celsius (4.1 degrees Fahrenheit) above those recorded from 1951-1980. As the Arctic warms, imperiling its biodiversity and indigenous people, researchers are increasingly concerned that the region will hit climatic tipping points that could severely impact the rest of the world. A recent commentary in Nature Climate Change highlighted a number of tipping points that keep scientists awake at night.
“If set in motion, [tipping points] can generate profound climate change which places the Arctic not at the periphery but at the core of the Earth system,” Professor Duarte, a climatologist with the University of Western Australia’s Ocean Institute and co-author other paper, said in a press release. “There is evidence that these forces are starting to be set in motion. This has major consequences for the future of human kind as climate change progresses.”
One of the tipping points is sea ice loss. The Arctic wasn’t just relatively hot last year—beating the previous record set in 2010 by 0.17 degrees Celsius (0.3 degrees Fahrenheit)—it also experienced the lowest sea ice volume yet recorded, and the second-lowest extent. Sea ice is essential to many Arctic species, from polar bears to walrus, and narwhals to seals. In just over 30 years, sea ice volume has dropped precipitously, declining by 76 percent from 1979 (16,855 cubic kilometers) to 2011 (4,017 cubic kilometers). This loss of sea ice also leads to greater regional and global warming, as the Arctic’s sea reflects the sun’s light back into space, cooling not only the region but the world.
The Arctic as viewed by NASA’s MODIS Satellite in June 2010. Greenland is the bright island on the bottom-left.
Sea ice loss may also be having a direct impact on weather in the mid-latitudes. In fact, recent research has suggested that, perhaps unintuitively, the extreme cold spell experienced by Europe this winter was linked to the sea ice decline in the Arctic. Researchers argue that the Arctic Oscillation, which is partially responsible for weather conditions in the Northern Hemisphere in winter, has become unhinged by the sea ice decline, causing more extreme winters, such as Europe’s cold spell and the massive blizzards that hit the U.S. in 2009 and 2010.
But it’s not just sea ice loss that has produced stark concerns: greenhouse gases from thawing permafrost could be just as disastrous. A study published in Nature late last year warned that greenhouse gas emissions due to permafrost thaw could equal the amount currently emitted by deforestation worldwide, a significantly larger estimate than has been put forward before. Moreover, since permafrost thaw emissions include methane, a more potent greenhouse gas than carbon, it could have an impact 2.5 times larger than deforestation overall.
“The larger estimate is due to the inclusion of processes missing from current models and new estimates of the amount of organic carbon stored deep in frozen soils,” co-author Benjamin Abbott, a University of Alaska Fairbanks graduate student, explained in a press release. “There’s more organic carbon in northern soils than there is in all living things combined; it’s kind of mind boggling.”
University of Florida researcher Edward Schuur says he doesn’t expect permafrost greenhouse gas emission to trump anthropogenic (human-caused) greenhouse gas emissions anytime soon, however they could become “an important amplifier of climate change.”
Polar bears approach a U.S. attack sub 280 miles from the North Pole in an encounter that would have been unimaginable a century ago. As the sea ice melts and the Arctic warms, many nations see not a climate warming, but an opportunity to exploit the region for resources. Photo by: U.S. Navy.
Further tipping points include an input of freshwater into the Atlantic Ocean from melting ice and glaciers, already increased by 30 percent, which Durate says “may affect the whole ocean current system and, as a result, the climate at a regional level.”
Governments have responded to warming in the Arctic with a resource race. Governments with Arctic territories plan to drastically expand oil and gas exploitation, utilize new shipping routes, and increase mining. The industrialization of the Arctic, according to Duarte, may only accelerate impacts on the fragile region and push tipping points.
“[Arctic tipping points] represents a test of our capacity as scientists, and as societies to respond to abrupt climate change,” Duarte said. “We need to stop debating the existence of tipping points in the Arctic and start managing the reality of dangerous climate change. We argue that tipping points do not have to be points of no return. Several tipping points, such as the loss of summer sea ice, may be reversible in principle—although hard in practice. However, should these changes involve extinction of key species—such as polar bears, walruses, ice-dependent seals and more than 1,000 species of ice algae—the changes could represent a point of no return.”
The solution, Durate says, is to cut the fossil fuel emissions that are causing climate change.
CITATIONS: Carlos M. Duarte, Timothy M. Lenton, Peter Wadhams, Paul Wassmann. Abrupt climate change in the Arctic. Nature Climate Change, 2012; 2 (2): 60 DOI: 10.1038/nclimate1386.
Schuur, Edward A. G.; Abbott, Benjamin. Climate change: High risk of permafrost thaw. Nature. 480, 32–33. 2011. doi:10.1038/480032a.
A NASA animation showing regional temperature changes on a map of the Earth from 1880-2011. On the map, blues represent temperatures lower than baseline averages, while reds indicate temperatures higher than the average. As the 131 years pass, the map turns from bluish-white to increasingly yellow and red. Notice the Arctic over the last 30 years. Caused by the burning of fossil fuels, deforestation, agricultural practices, and other human impacts, climate change has currently raised global temperatures 0.8 degrees Celsius (1.44 degrees Fahrenheit) higher than the Industrial Revolution average.
(02/09/2012) Drilling in the Arctic waters of the U.S. may become as contested an issue as the Keystone Pipeline XL in up-coming months. Scientists, congress members, and ordinary Americans have all come out in large numbers against the Obama Administration’s leases for exploratory drilling in the Beaufort Sea and the Chuckchi Sea.
(11/30/2011) As officials meet at the 17th UN Climate Summit in Durban, South Africa, the world continues to heat up. The UN World Meteorological Organization (WMO) has announced that they expect 2011 to be the warmest La Niña year since record keeping began in 1850. The opposite of El Nino, a La Niña event causes general cooling in global temperatures.
(10/06/2011) The disintegration of the Arctic sea ice, which hit the second lowest record this year, is forcing a number of Arctic animals to change their behavior.
(09/29/2011) Following the Obama administration’s approval of Royal Dutch Shell to drill in the Arctic’s Beaufort Sea, a wide-swathe of environmental have filed a lawsuit to stop the drilling, which could begin as early as next summer. Those filing the lawsuit today blasted Shell for what they perceived as a pathetic oil spill response plan, and the Obama administration for acquiescing to the big oil company.
(09/28/2011) After the Arctic sea ice extent hit its second lowest size on record this summer—or lowest (depending on the source)—comes another climate change shocker: in the past six years Canada’s millennia-old ice shelves have shed nearly half their size. One ice shelf—the Serson shelf—is almost entirely gone, while another—the Ward Hunt shelf—has split into two distinct shelves. The ice shelves have lost 3 billion tons in this year alone.
(09/12/2011) Arctic sea ice cover fell to its lowest level on record, report researchers from the University of Bremen.
(09/01/2011) Recent, unprecedented walrus haul-outs and increased instances of long-distance swims by polar bears show the direct impacts on wildlife of dwindling Arctic sea ice from climate change. These threatened species also face the prospect of offshore drilling in the Arctic after the Obama Administration recently approved a number of plans to move forward on oil exploration. At least 8,000 walruses hauled out on an Alaskan beach along the Chukchi Sea on August 17. Only a day before, the U.S. Geological Survey announced it would begin tagging walruses near Point Lay, Alaska to study how a lack of sea ice is affecting the species.
(08/10/2011) Average Arctic sea ice extent hit a new record low for July according to the National Snow and Ice Data Center (NSIDC).If the melt continues apace, the sea ice extent could hit its lowest point since record keeping by satellite began 32 years ago. However, ice loss slowed through the second half of July as weather grew colder in the Arctic, and by the end of the month was slightly above conditions in 2007, in which the lowest sea ice extent ever was measured.
(08/08/2011) Less than a year and a half after the oil spill in the Gulf of Mexico, the Obama administration has bucked warnings from environmentalists to grant preliminary approval to oil giant, Royal Dutch Shell, to drill off the Arctic coast. Exploratory drilling will occur just north of the western edge of the Arctic National Wildlife Refuge (ANWR) in the Beaufort Sea, home to bowhead and beluga whales, seals, walruses, polar bears, and a wide variety of migrating birds.
(07/21/2011) Arctic sea ice could hit a record low by the end of the summer due to temperatures in the North Pole that are an astounding 11 to 14 degrees Fahrenheit (6 to 8 degrees Celsius) above average in the first half of July, reports the National Snow and Ice Data Center (NSIDC). Already the sea ice extent is tracking below this time in 2007, which remains the record year for the lowest sea ice extent. The sea ice hits its nadir in September before rebounding during the Arctic winter.