Tuesday, February 24, 2015

The GW Factor


BRT has talked about GW ad nauseum but one article, posted in March of 2014, titled The-Thermo-haline-et-al , explains how the South Pole, in large part, drives the world's weather via Antarctic bottom water in conjunction with the Waddell Sea Polynya.

Seems other researchers are capping on these findings as seen in the IFLS piece titled, What's Going on with the Weather?

Jet streams exist because of differences in air temperature. In the case of the polar jet stream, which is responsible for most of the weather we experience around the middle-latitudes of the northern hemisphere, it’s the cold Arctic butting against warmer areas to the south that drives it. (A more in-depth explanation can be found here.) Anything that affects that temperature difference will affect the jet stream.

This is where climate change comes in: the Arctic is warming much faster than elsewhere. That Arctic/mid-latitude temperature difference, consequently, is getting smaller. And the smaller differential in temperatures is causing the west-to-east winds in the jet to weaken.

Strong jets tend to blow straight west to east; weaker jets tend to wander more in a drunken north/south path, increasing the likelihood of wavy patterns like the one we’ve seen almost non-stop since last winter.

When the jet stream’s waves grow larger, they tend to move eastward more slowly, which means the weather they generate also moves more slowly, creating more persistent weather patterns.

Nice to see BRT's ahead of the curve on this one. :)


NOAA's shot of the Jet Stream circa the Winter of 2015.



Post a Comment