Arctic Ocean ice floes photo courtesy NOAA
Arctic air temperatures are at a record 9 degrees F (5 degrees C) above normal this autumn, because of the major loss of sea ice in recent years, according to the U.S. National Oceanic and Atmospheric Administration (NOAA).
The air temperature is but one example of changes in the Arctic climate. A near-record loss of summer sea ice and a melting of surface ice in Greenland are among other evidence of continued warming, according to an annual review of conditions in the Arctic issued last week by NOAA and its university, agency, and international partners.
“Changes in the Arctic show a domino effect from multiple causes more clearly than in other regions,” said James Overland, an oceanographer at NOAA’s Pacific Marine Environmental Laboratory in Seattle and a lead author of the Arctic Report Card. “It’s a sensitive system and often reflects changes in relatively fast and dramatic ways.”
The loss of sea ice allows more solar heating of the ocean. That warming of the air and ocean affects land and marine life, and reduces the amount of winter sea ice that lasts into the following summer.
The Arctic Report Card, introduced by NOAA’s Climate Program Office in 2006, establishes a baseline of conditions in that region in the 21st century and provides a way of monitoring the often quickly changing conditions.
It is updated annually in October and tracks the Arctic atmosphere, sea ice, biology, ocean, land and Greenland.
In this year’s Report Card, three of the six areas (atmosphere, sea ice, and Greenland) are coded red, indicating that the changes are strongly attributed to warming. The three remaining areas (biology, ocean, land) are coded yellow, indicating mixed signals.
The 2007 Report Card had two red areas (atmosphere and sea ice) and four coded yellow. The year 2007 was the warmest on record for the Arctic, continuing a general Arctic-wide warming trend that began in the mid-1960s.
“The Arctic Report Card is one of the few opportunities for a team of researchers to work together to provide a very broad look at the state of the Arctic system,” said the report’s chief editor Jackie Richter-Menge from the USACE Cold Regions Research and Engineering Laboratory in Hanover, New Hampshire. “The information combines to tell a story of widespread and, in some cases, dramatic effects of an overall warming of the Arctic system.”
The report’s other contributing lead authors are from the Woods Hole Oceanographic Institute, the Geophysical Institute of the University of Alaska in Fairbanks, Byrd Polar Research Center at Ohio State University, and Environment Canada.
Arcitc Report Card 2008 (NOAA)
A failing grade (Grist)
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