Stratospheric Warming linked to our weather
Meteorologists at Freie Universität have found a correlation between warming in the stratosphere and cold or warm winter periods. They observed that there is an increased number of stratospheric warmings, when the heat flow from the North Atlantic into the atmosphere is increased. Trends for winter temperatures can be derived from these new findings.
"This could mean that in Europe there will increasingly be periods lasting several decades with predominantly colder winters alternating with periods of warmer winters," says Semjon Schimanke, who led the research, reported in the journal Geophysical Research Letters. The meteorologists expect that in the long term their research will help weather forecasters make more accurate predictions.
The phenomenon of stratospheric warming was first discovered in 1952 by Professor Richard Scherhag at the Institute of Meteorology, Freie Universität Berlin. It appeared in the scientific literature as the "Berlin phenomenon." In the meantime, these events are referred to as "sudden stratospheric warmings," and 30 have been registered so far.
On average, sudden stratospheric warmings occur in every second winter, and they are very unevenly distributed over the observation period. Only a single stratospheric warming occurred between the winters of 1988/1989 and 1997/1998, while nine have been registered since the beginning of this millennium. So far there has been no explanation. With their new research, the meteorologists at Freie Universität have shown that the intermittent sudden stratospheric warmings are a consequence of the interaction between the North Atlantic, the troposphere, and the stratosphere. They found that an increased number of sudden stratospheric warmings occur when the heat flux from the North Atlantic into the atmosphere is increased.
Article continues: http://www.sciencedaily.com/releases/2011/01/110121081051.htm