Change in the Arctic

• Main Authors: Helene Hewitt, Sheldon Bacon, Danny Feltham, Chris Foll, Tim Graham, Dan Hodson, Laura Jackson, Sarah Keeley, Ann Keen Seymour Laxon, Axel Schweiger, Ann Keen, Seymour Laxon, Alison Mclaren, Matt Menary, Jeff Ridley, Adam Scaife, Doug Smith, Meric Srokosz, Alex West, Richard Wood
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2012
• Subjects: Arctic; Arctic Ocean; Climate change; Sea ice
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.397.6690; http://www.metoffice.gov.uk/media/pdf/p/i/HCTN_91.pdf

Sea ice decline is iconic of climate change in the Arctic. Sea ice reductions represent the integrated changes which are taking place in both the ocean and atmosphere. Arctic surface temperature is also warming. The presence of sea ice determines the accessibility of the Arctic Ocean and its presence can also affect European and global climate. Arctic sea ice extent has declined at an annual rate of over 4 % per decade since satellite records began in 1979. This rate is faster in the summer season and there is evidence that the rate of loss has increased over the latter half of the satellite period. There is also evidence that the ice has thinned at a rate of approximately 60cm per decade. However, the heating required to melt the ice at this rate is very small- just 1 W/m 2 representing only 2 % of the magnitude of the seasonal cycle, implying that observing and modelling the mechanisms underlying these changes will be challenging. The record lowest ice extent was observed in September 2007. However, in any particular summer, the sea ice extent can be influenced by the state of the sea