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Tuesday, September 25, 2012

Stratospheric vortex effect on the deep sea


Modeling carried supercomputer showed that the stratospheric vortex affect the depth of the oceans and therefore play a role in shaping the Earth's climate, according to "Kompyulenta" referring to the publication in the journal Nature Geosciences.

Events in the stratosphere at an altitude of 10-50 km are reflected in what is happening in the troposphere below it. It is also known that the behavior of the troposphere affects the circulation of the oceans, which in turn determines the climate. One of the earlier studies hinted that the events in the stratosphere can directly affect the oceans, but the conclusion was based on only one climate model, which also covered a relatively short period of 260 years.


Delve deeper into the problem of attempted Rayhler Thomas of the University Of Utah (USA) and his colleagues. The scientists used a famous model, developed by the National Oceanic and Atmospheric Administration (USA): it incorporated the data for four millennia. The simulation results were compared with the statements collected in the last thirty years. The result has been found surprising connection between stratospheric winds and ocean currents at a depth of 2 km. The researchers emphasize that the conclusions supported by the data of 18 other models.
                                                                                                                                        
It was found that on average, every two years, suddenly heats the stratosphere for a few tens of degrees. This leads to the fact that the Arctic polar vortexes, which are stratospheric winds, rushing up to 130 km / h, could weaken or change direction (usually twisted counterclockwise) for about two months. Calculations show that this warming is dramatically disturbs the surface of the ocean, affecting the Atlantic meridional circulation (Atlantic Meridional Overturning Circulation) - a system of currents that came on the conveyor belt, which mixes all the world's oceans.

"The impact of the stratosphere explains about 30% of the variation found in the ocean - said Rayhler. - It turned out that the Atlantic meridional circulation is the Achilles' heel, located in the North Atlantic Ocean, south of Greenland. “The region, he said, responding to even a relatively small warming or cooling of the atmosphere, and the water temperature (or rather, how deeply it sinks in this time) plays a role for all of the thermohaline circulation.

The results show that climate models should stop ignoring the stratosphere. At the same time, it remains unclear how much the stratosphere affects climate. Its sudden heating causes the heat rising from the troposphere, so it is tempting to say that in fact it was all my fault troposphere. However Rayhler sure that the stratosphere is necessary to enhance the effect

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