Canada; s Top Ten Weather Stories for 2011

摘要

According to Environment Canada and the National Snow and Ice Data Centre in Colorado, sea ice covering the Arctic Ocean declined to its second-lowest extent on record in September 2011. The near-record ice melt was surprising owing to the absence ofthe unusual warm weather and oceanic conditions that contributed to the super melt in 2007. Thin, year-old ice less than a metre thick that now dominates the Arctic ice pack is much more prone to melting than durable, multi-year ice. Since 1979, September Arctic sea ice extent has declined by 12 per cent per decade. Additionally, the five greatest ice retreats of the satellite era have occurred in the past five years.