Record summer sea ice loss, low spring snow cover and the melting of Greenland's ice sheet were just a few of the remarkable events that occurred in the Arctic during 2012, according to a new report on the record-breaking year in the Arctic from the National Oceanic Atmospheric Administration (NOAA)
Scary New Report on Arctic Ice
Scary New Report on Arctic Ice
Arctic Snow Melt Adds to Global Concern
All of this happened even with air temperatures that were not unusually higher-than-average this year compared to the last decade.
"The Arctic is changing in both predictable and unpredictable ways, so we must expect surprises," said Jane Lubchenco, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator. Lubchenco added, "The Arctic is an extremely sensitive part of the world and with the warming scientists have observed, we see the results with less snow and sea ice, greater ice sheet melt and changing vegetation."
Below is a look at the findings in the latest "Arctic Report Card", which has been updated each year by NOAA since 2006:
- Snow cover- Record low snow cover extent in the Northern Hemisphere was set in June 2012. Eurasia recorded a record low in May 2012.
- Sea ice- Arctic sea ice extent fell to a new record low in September, beating the old record low set in 2007. Measurements by satellite have been collected since 1979.
- Greenland ice sheet- A rare, nearly ice sheet-wide melt event occurred in July on the Greenland ice sheet. This covered about 97 percent of the sheet on a single day.
- Vegetation- The tundra is greener and there is more above-ground growth. From 2003-2010, the growing season grew in length across much of the Arctic.
- Ocean- Sea surface temperatures remain warmer-than-average in the summer near the growing ice-free margins.
- Weather- There were three extreme weather events. An unusual cold spell from late January to early February 2012 in Eurasia. In addition, two record storms with very low pressures and strong winds occurred near western Alaska in November 2011 and north of Alaska in August 2012.
Arctic Unlikely to Return to its Former State Quickly
NOAA says that the record-breaking year also indicates that it is unlikely that conditions can quickly return to their former state.
(MORE: Ice sheets melting faster)
"The record low spring snow extent and record low summer sea ice extent in 2012 exemplify a major source of the momentum for continuing change," added Jeffries. "As the sea ice and snow cover retreat, we're losing bright, highly reflective surfaces, and increasing the area of darker surfaces-both land and ocean-exposed to sunlight. This increases the capacity to store heat within the Arctic system, which enables more melting-a self-reinforcing cycle."
"The record low spring snow extent and record low summer sea ice extent in 2012 exemplify a major source of the momentum for continuing change," added Jeffries. "As the sea ice and snow cover retreat, we're losing bright, highly reflective surfaces, and increasing the area of darker surfaces-both land and ocean-exposed to sunlight. This increases the capacity to store heat within the Arctic system, which enables more melting-a self-reinforcing cycle."
To view the entire report card from NOAA, click here.http://www.weather.com/news/arctic-breaks-records-report-card-20121206
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