March 27, 2013
Loss Of Arctic Ice May Be Cause Of This Chilly Spring
Brett Smith for redOrbit.com - Your Universe Online
Have you been experiencing the coldest spring weather in recent memory? It´s probably because of global warming.
"Ironically ... as the ice pack retreats and the Arctic heats up, there's a counteracting tendency in middle latitudes for colder winters, as well as hotter summers," said Stephen Vavrus,“¯senior scientist at the Nelson Institute for Environmental Studies at the University of Wisconsin.
The upper atmospheric winds, known as the jet stream, blow weather systems from west to east across the Northern Hemisphere, preventing any one air mass from staying in one place for very long. The drastic reduction in sea ice has affected the activity of the jet stream by allowing Arctic waters to absorb more heat energy from the sun, says Vavrus. This heating effectively impedes the westerly jet stream, resulting in a slow meandering air current instead of a quicker and more direct one.
"When that happens during winter, there's less warm air that gets transported over land," Vavrus explained. "That essentially helps to refrigerate the land during the wintertime and we get snow and more cold and more extreme cold as well."
Vavrus´ theory is backed by a recent study from the National Oceanic and Atmospheric Administration (NOAA) which found that Arctic warming had influenced weather across the northern hemisphere.
"With more solar energy going into the Arctic Ocean because of lost ice, there is reason to expect more extreme weather events, such as heavy snowfall, heat waves, and flooding in North America and Europe," said the NOAA scientists.
"Simulations suggest that these summertime highs will intensify in the twenty-first century as a result of an increase in atmospheric greenhouse gas concentrations,” the scientists added.
In addition to the precipitous drop in sea ice, studies have shown that warming temperatures threaten to release massive amounts of carbon that have been trapped for thousands of years in Arctic permafrost. The release of this gas would only add further fuel to the cycles that are driving climate change.
After seeing the maximum sea ice levels during the 2013 winter months, climate scientists said it would be difficult to predict how far the ice would recede in the summer. Last winter, the sea ice was found to be the 9th-lowest on record, yet the all-time summer low followed six months later. This year´s maximum is lower than 2012´s, but the unpredictable prevailing winds and ocean currents make predictions highly difficult. If scientists don´t see a record low this summer, they expect it will happen soon as they believe the Arctic Ocean will eventually be almost ice-free for much of the summer.
While an ice-free Arctic Ocean could translate into a nightmare scenario, the receding ice could be good news for shipping companies. Many are already looking into“¯Arctic shortcuts“¯from Asia to Europe. NOAA is also planning on redrawing its charts to assist commercial ships in navigating the changing waters.