Colossal Storm Hits Alaska
14.11.2011 - Atmosphere & Space, Water & Oceans, Arctic
During the second week of November, a major storm that meteorologists refer to as an “extra tropical cyclone” hit Alaska’s western coastline, pounding the region with heavy snow and unusually strong winds. The storm displaced thousands of coastal residents and left behind widespread damage, including flooding, power outages and destroyed roofs.
During its peak, the cyclone spanned some 2,700 kilometres. Not since the mid 1970s has Alaska seen a storm of such magnitude. However at that time, sea ice build-up was able to protect many towns along the coast from coastal erosion. This time, most of the Bering and Chukchi Sea coasts were ice-free, despite it being mid-autumn, leaving the shoreline was less protected than it had been in the past and vulnerable to coastal erosion. The extent and thickness of sea ice has been decreasing in the Arctic, due at least in part to climate warming, according to scientists.
According to meteorologists, autumn weather conditions are responsible for the formation of these kinds of strong storms in the North Pacific. The contrasting cold air from the North Pole in mid-October and the warmth released to the atmosphere by the North Pacific provided the energy to drive the storm.
Over the course of the past several years, various studies have shown there has been an increase in the occurrences of intense storms in the Northern Hemisphere over the past century, with a noticeable rise from the mid-1960s onwards, as average global temperature has increased. While some scientists believe that the occurrences of winter storms will diminish as the climate warms, they say that their intensity may increase and start appearing at higher latitudes than normal.