The shrinking expanse of Arctic sea ice is increasingly vulnerable to summer sunshine. New research finds that unusually sunny weather contributed to last summer’s record loss of Arctic ice, while similar weather conditions in past summers did not have comparable impacts. "In a warmer world, the thinner sea ice is becoming increasingly sensitive to year-to-year variations in weather and cloud patterns. A single unusually clear summer can now have a dramatic impact." Summer sunshine produces more pronounced melting than in the past, largely because there is now less ice to reflect solar radiation back into space. As a result, the presence or absence of clouds now has greater implications for sea ice loss. Last summer's loss of Arctic sea ice set a modern-day record, with the ice extent shrinking to a minimum of about 1.6 million square miles (4.1 million square kilometers) in September. That was 43% less ice coverage than in 1979, when accurate satellite observations began. In addition to solar radiation, other factors such as changes in wind patterns and possibly shifts in ocean circulation patterns also influence sea ice loss. In particular, strong winds along regions of sea ice retreat were important to last year's loss of ice.
Nature has a way of continually surprising us and inspiring awe within us, and it seems there are just as many fantastical wonders t...