Monday, December 15, 2008

A Taste of the Arctic

Those of us who live in the Temperate and Tropical Zones cannot truly appreciate the conditions faced by humans and other animals that inhabit the polar regions. This latest Arctic outbreak, triggered by a broad dip in the jet stream, is giving us a taste of life at the Poles. Extreme cold has invaded the Northern Plains, where morning lows hovered at 20-30 degrees F below zero; add in the wind effect and we're talking serious cold!

The development of extreme cold requires a lack of solar heating and limited cloud cover; the latter permits heat to radiate into space and is a common feature of the dry polar climate. In the Arctic, a perpetual night began in mid November and will last until late January; the only warming that they will experience is via southerly winds ahead of polar fronts. In a twist of fate, their relief is at our expense as the intense, Arctic cold is displaced to the south; on the positive side, this polar air is extremely dry and precipitation, in the form of rain, snow or ice, is generally short-lived, moving off with the frontal boundary as the cold, dense air rushes to the south and east.

Looking out from my office window this morning, I watched a snowball moon set behind a flat shelf of snow-white clouds. The temperature was 6 degrees F.