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View Full Version : Weakened thermohaline circulation will increase snow cover over Europe


tookitook
21st December 2005, 11:23 AM
credits to: http://www.mpimet.mpg.de/en/web/index.html

AGU Journal Highlight

Global climate models and paleo-observations have associated periods of weak or absent global thermohaline circulation (THC) with widespread cooling around the North Atlantic. However, the low spatial resolutions of past climate models prevented detailed analyses of the weakened circulation’s effects on specific locations in Europe. To study this, Jacob et al. used a high resolution regional climate model nested into a global climate model to perform a THC slowdown experiment through imposing additional freshwater to the northern Atlantic, corresponding to one-sixth of the Greenland ice sheet melting over 100 years. According to the model hierarchy, this reduced the strength of the THC by half, changing atmospheric circulation and enhancing maritime climate influences over Europe. Their model system predicted more than 3°C of surface cooling over the North Atlantic, forcing winter temperatures in northern Europe to drop by 1.5°C or more. Precipitation also decreased in their model, especially in summer. The remaining precipitation manifested as snow, increasing the albedo of Scandinavia, northern Germany and Britain, and mountainous areas in central Europe. If these scenarios occur, the authors noted that energy consumption in Europe would likely increase due to humans responding to such cold temperatures.

Citation:
Jacob, D., H. Goettel, J. Jungclaus, M. Muskulus, R. Podzun, and J. Marotzke (2005), Slowdown of the thermohaline circulation causes enhanced maritime climate influence and snow cover over Europe, Geophys. Res. Lett., 32, L21711, doi:10.1029/2005GL023286

Contact:

Dr. Daniela Jacob
Max Planck Institute for Meteorology
Phone: +49 40 41173 313
e-mail (jacob@dkrz.de)

December 12, 2005 http://www.mpimet.mpg.de/en/web/img/trans.gif

rocksea
21st December 2005, 01:07 PM
i heard winters are colder than before in europe now. is it so?
how is it in your part of russia?

tookitook
21st December 2005, 06:00 PM
I would say that they become much wormer :)

rocksea
22nd December 2005, 06:19 AM
I would say that they become much wormer :)warmer in your part of russia, you mean, right?

praveen
22nd December 2005, 11:41 AM
I have some doubts about this. If more fresh water comes in north atlantic (may be by melting of ice), it will becomes more fresh. So there THC will starts reducing and then conveyer belt mechanism reduces the tracnsport of warm water from low lattitude to high latitude, So obiviously high latitudes become much colder.

But if it is so, then the ice formation will start again in that reduced temperature. :eek: .Then north atlantic become more dense and the THC will come back.

pls some one make me clear about this.

koldunovn
22nd December 2005, 02:03 PM
If we will have increasing or decreasing of ice formation in Europe or surrounding regions – it will not affect convection in the Greenland Sea too much. The main source of ice in the Arctic Ocean is Laptev Sea. It’s not a fact that decreasing of temperature in Europe due to Golfstream’s shutdown will affect ice formation in the Laptev Sea.