![]() ![]() January 2016's remarkable phase transition of Arctic oscillation was driven by a rapid tropospheric warming in the Arctic, a pattern that appears to have increased surpassing the so-called stratospheric sudden warming. That warm pulse quickly dissipated, but it was followed by a series of intense North Atlantic cyclones that sent very mild air poleward, in tandem with a strongly negative Arctic oscillation during the first three weeks of the month. Just before New Year’s, a slug of mild air pushed temperatures above freezing to within 200 miles of the North Pole. Hand in hand with the skimpy ice cover, temperatures across the Arctic have been extraordinarily warm for midwinter. įor January 2016, the satellite-based data showed the lowest overall Arctic sea ice extent of any January since records began in 1979. Wave action breaks up sea ice, and thus could become a feedback mechanism, driving sea ice decline. This is a new phenomenon for the region, since a permanent sea ice cover normally prevents wave formation. Scientists recently measured sixteen-foot (five-meter) wave heights during a storm in the Beaufort Sea in mid-August until late October 2012. By 2013, ice that age was only 7% of all Arctic sea ice. ![]() In 1988, ice that was at least 4 years old accounted for 26% of the Arctic's sea ice. The amount of multi-year sea ice in the Arctic has declined considerably in recent decades. Observation with satellites shows that Arctic sea ice area, extent, and volume have been in decline for a few decades. This is primarily an issue in summer months. This metric is used to address uncertainty in distinguishing open sea water from melted water on top of solid ice, which satellite detection methods have difficulty differentiating. Sea ice extent is defined as the area with at least 15% of sea ice cover it is more often used as a metric than simple total sea ice area. Typical data visualizations for Arctic sea ice include average monthly measurements or graphs for the annual minimum or maximum extent, as shown in the adjacent images. Arctic Sea ice maximum is the day of a year when Arctic sea ice reaches its largest extent near the end of the Arctic cold season, normally during March. The Arctic sea ice minimum is the day in a given year when Arctic sea ice reaches its smallest extent, occurring at the end of the summer melting season, normally during September. Arctic Sea Ice refers to the area of the Arctic Ocean covered by ice. The Arctic Ocean is the mass of water positioned approximately above latitude 65° N. January 1, 2013, to September 10, 2016, when the sea ice reached its annual minimum extent Both the disappearance of sea ice and the resulting possibility of more human activity in the Arctic Ocean pose a risk to local wildlife such as polar bears. Shipping is more often possible in the Arctic now, and expected to increase further. It is hypothesized that sea ice decline also makes the jet stream weaker, which would cause more persistent and extreme weather in mid-latitudes. Sea ice loss is one of the main drivers of Arctic amplification, the phenomenon that the Arctic warms faster than the rest of the world under climate change. In September 2020, the US National Snow and Ice Data Center reported that the Arctic sea ice in 2020 had melted to an area of 3.74 million km 2, its second-smallest area since records began in 1979. The IPCC Sixth Assessment Report (2021) stated that Arctic sea ice area will likely drop below 1 million km 2 in at least some Septembers before 2050. The region is at its warmest in at least 4,000 years and the Arctic-wide melt season has lengthened at a rate of five days per decade (from 1979 to 2013), dominated by a later autumn freeze-up. It is also thought that summertime sea ice will cease to exist sometime during the 21st century. The decline of sea ice in the Arctic has been accelerating during the early twenty‐first century, with a decline rate of 4.7% per decade (it has declined over 50% since the first satellite records). Global warming, caused by greenhouse gas forcing is responsible for the decline in Arctic sea ice. It has been melting more in summer than it refreezes in winter. Sea ice in the Arctic has declined in recent decades in area and volume due to climate change. ![]() Decline in arctic sea ice volume from 1979 to 2022 ![]()
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