Treasna na dTonnta
Warming temperatures in the Arctic The Arctic and Antarctic have felt the most dramatic rises in average annual temperatures by as much as 3 degrees Celsius. In the Arctic multi-year sea ice, some up to 10 years old has been lost due to warming and although ice re-forms each winter, single year ice is not as compacted and melts faster in spring and summer. Ice in the polar regions reflects the sun’s rays and solar radiation is deflected back into space. Open water however absorbs heat and as the ice melts, the warming is accelerated. In mid-September 2012 it was reported that the extent of sea ice had collapsed to just 3.5million km2, 40% of its usual extent measured in the 1970’s. Scientists also expect the Arctic Ocean to be largely free of summer ice by 2020.
Fig.4. Depiction of Arctic sea ice on Sept. 12, 2013 just before the estimated sea ice extent hit its annual minimum. The yellow line shows the 30-year average minimum extent. Image Credit: NASA Goddard’s Scientific Visualization Studio/Cindy Starr
Newsletter of the Irish Sea Kayaking Association