This is a very instructive finding inasmuch as it clearly delineates a mechanism for inflows of energy into the Arctic and establishes proxies that justify monitoring. We discover that ice flow speed is a critical measure and a direct reflection of climatic energy inputs. This should be fairly easy to monitor.
I do not get a sense that the storm track data provides quite the quality of resolution needed to fully support the assertions over the entire time span suggested. That is no matter because the direction is clear and more recent data is much better.
Rather importantly, we have a clear and variable mechanism for transferring heat into the Arctic that can be studied by itself. It needs to be respected.
This does not link Arctic warming to some global warming theory even though the concept expressed is that an expansion of tropical warm water forces the storm tracks north. Perhaps this is linked to a long cycle hurricane activity buildup. Both seem to be around forty years in length.
Certainly there seems to be a forty year cycle with hurricanes, but this is the first time it could be linked to an Arctic warming.
Rather more interesting, we can propose a switching mechanism at work. Heat is generated in the warm water zone around the equator, forming large tropical storm systems that travel west ward. They either impact directly on the Gulf coast or part of the Atlantic seaboard, or alternately track the Gulf Stream north.
If the weather system impacts land, most of the contained energy is lost very quickly over land and is contained within the temperate belt. How any of that energy might migrate into the Arctic is not overly apparent.
However, energy tracking with the Gulf Stream will enter the Arctic. Therefore anything that increases storm flow into the Arctic will obviously raise the temperature in the Arctic. This is what seems to have happened. It is possible to argue that surplus heat of the coast of Africa forces more storms into the Arctic.
In the event, we have visible and measurable mechanism that explains why a certain amount of excess heat has been finding its way north. It is not linear and appears to be still at full strength. It is also just subtle enough to be associated with the very subtle variation in solar output, or even that of the CO2 hypothesis.
It is suggesting that a slight global heat increase energizes this storm route to shift heat directly into the Arctic, to some degree bypassing the temperate climes. Or some other mechanism might just switch it on for no particularly good reason. Here is where we would like to have better data from the past two centuries.
Warming Leads To A Stormier Arctic
Submitted by Darpana Kutty on Thu, 10/09/2008 - 06:40.
A new NASA study has put forward the finding that in the past 50 years, the Arctic has become stormier because of the warming climate that has actually fastened the speed of drifting sea ice.
It was actually being predicted by the climate scientists from a long period of time, who adhered the model results that there would be an increase in the frequency and intensity of Arctic storms due to the warming climate, since it led to the continuous warming of the sea waters.
But now, 56 years of data of the paths taken by the storms and annual data on general storm activity, was analyzed by a team of climate scientist, who then concluded that the Arctic storm activity from 1950 to 2006 had been following an increasing trend.
Other than this, the tram also studied the data on ice drift in the Arctic collected during the same 56-year period and discovered that the speed of sea ice movement along the Arctic Ocean's Transpolar Drift Stream from Siberia to the Atlantic Ocean has also caught speed.
The researchers have formed a link between the increase in Arctic storminess and the sea ice drift speeds, since it has been learnt that wind at the ocean surface is driving force behind the movement of sea ice. These findings have been published in the October 3 issue of the journal Geophysical Research Letters. Further the results of the study can strengthen the fact that changes in Arctic Ocean play a crucial role in global ocean circulation and climate change.
Sirpa Hakkinen of Nasa's Goddard Space Flight Center in Greenbelt, Maryland and a team member said, “Gradually warming waters have driven storm tracks — the ocean paths in the Atlantic and Pacific along which most cyclones travel — northward. We speculate that sea ice serves as the 'middleman' in a scenario where increased storm activity yields increased stirring winds that will speed up the Arctic's transition into a body of turbulently mixing warm and cool layers with greater potential for deep convection that will alter climate further.”
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