Monday, December 17, 2007

Cold Winters and the Arctic

I must admit that as anyone who is imbued with the precepts of science, that I always reach for cause and effect relationships. When they fail to materialize, one merely looks deeper, often forgetting that they may not be that well linked. A great example of this is the ongoing effort to link a very real problem of excess CO2 production that must be properly offset sooner or later, to the not so convincing natural problem of global temperature variation. My real fear is that this linkage is a two edged sword. A normal reversal in the current warm spell can be used to defer efforts to manage the CO2 problem.

This winter, our ideas about climate change are getting a really good stress test and it will be very interesting to see how it shakes out.

We have had a unseasonably cold winter to date and we are getting the storms to go with it. And this is hot on the heels of the warmest Arctic summer ever. All of a sudden a clear cause and effect relationship is junk. A warm Arctic does not produce a succeeding warm winter in North America!

Did the new wind system shift more heat into the Arctic leaving less available for the mid latitudes? Will we see the same pattern next year?

We have seen one prospective cause and effect relationship crash. Will a cold mid latitude winter lower the heat influx into the Arctic resulting in a colder Arctic summer?

Is the shift in the wind regime going to sustain itself through another season? Is this new wind regime the engine for shifting mid latitude heat into the Arctic?

We have already seen a shift in Arctic conditions and the changes must be considered at least volatile since they appear to be outside the known range. This means that prior knowledge will be often misleading. The only thing that we can be sure of is that the current regime is not stable yet.

If we have a cold winter, yet the summer shows the same level of sea ice removal as last year, then we are likely seeing a new climate regime been established, which is my inclination anyway. In fact, it would confirm to me that the principal source of Arctic Sea Ice erosion comes from the surplus heat contained in the Gulf stream and that winds and atmospheric heat are largely helpers.

If we have a cold winter followed by a rebuilding of that same sea ice, then we have direct cause and effect relationship between continental winter climate and the successor summer climate, but no such relationship for the reverse.

Of course the factors that impact on the continental regime are ocean temperature regimes such as El Nino and La Nino.

The ebb and flow of heat out of the central latitudes continues to be poorly understood as demonstrated by the sheer folly of predicting the nature of the hurricane system each year. since 2005, we have obviously entered a quiet period as has happened in decades past.

We can presume that so much energy was drawn out of the equatorial waters in that season that it has not been able to recharge. And what sort of special confluence of events creates a major hurricane season? We do not know yet.

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