Today was on the chilly feeling side but that is only because we have become used to such mild weather...it was still several degrees above normal.
Meanwhile, in Washington D.C., the fast blooming cherry blossoms have loused up a lot of peoples' plans...
Let me see if there is a good story on this Spring on the internet--why has it been so warm?
This is from Discover Magazine website
Why This Winter is So Crazily Warm
Spring! Not.
Why this freaky weather? The answer is, basically, an extremely unusual jet stream over the last few months, Masters explains. The jet stream that defines weather in North America is controlled by the North Atlantic Oscillation and the Arctic Oscillation, climate patterns that reflect differences in sea-level pressure across certain stretches of the globe. And the pressure differences this year have been tremendous—for the North Atlantic Oscillation (NAO), this year saw the most extreme difference ever recorded in December, and the second most extreme for the Arctic Oscillation (AO).
This positive pressure difference has drawn warm air from the southwest over the Eastern US, rather than the usual chilly air from the Arctic. Last winter’s pressure differences were gigantic as well, but in the opposite, negative direction, so lots of cold air poured down and we had tons of snow. In fact, the last six years have been generally strange for the Arctic Oscillation, with the two most extreme negative values and two most extreme positive values on record.
But why?, you ask. Why have these oscillations been so weird? Unfortunately, Masters writes, we don’t really know why these variations happen. Addressing the elephant in the room—I’m looking at you, climate change—he says, “Climate models are generally too crude to make skillful predictions on how human-caused climate change may be affecting the AO, or what might happen to the AO in the future.” But he notes that there are links between solar activity and sunspots and positive values and between arctic sea ice loss and negative values. Whether this year’s strong positives are related to sunspots, though, isn’t clear.
Image courtesy of subflux / flickr
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