Nice graph.
What exactly is it a measurement of?
It’s a graph from the National Oceanic and Atmospheric Administration showing the arctic oscillation - a particular weather phenomenon I guess. It involves the jet stream, where high and low pressures are etc.
I just noticed it going off the scale negative in mid December, and have been reading about it a bit.
It seems they haven’t recorded it going this negative since the fifties, and it involves pretty much the entire Northern hemisphere getting colder, except for the west coast of the Americas.
If you are interested in climate I recommend this site:
What’s up with that. Here’s their post about what we are discussing:
The Arctic Oscillation Index goes strongly negative
http://wattsupwiththat.com/2009/12/28/the-arctic-oscillation-index-goes-strongly-negative/
Cheers.