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THURSDAY MARCH 15 - RECENT SUCCESS IN LONG-RANGE FORECASTING
At the American Meteorological Society conference back in January, there was a lot
of discussion about seasonal climate forecasting - that is, predicting trends in
temperature and precipitation months in advance. Until a few years ago, these
forecasts, which are issued routinely by the Climate Prediction Center, weren't
all that much better than educated guesses.
But during the winters from 1997 to 2000, these outlooks were better than any
seasonal forecasts that the Climate Prediction Center had ever issued. This recent
success can be traced to a decade of research on
El Nino and its flip side,
La Nina. When either of these Pacific Ocean
temperature anomalies is occurring,
as was the case during those winters, there's a somewhat predictable ripple effect
in the atmosphere to other parts of the globe, and long-range forecasters can exploit that.
The new challenge is identifying the keys to seasonal forecasting when neither
El Nino nor La Nina is in progress, as was the case leading up to this winter.
This has spurred new research into other atmospheric cycles that go by names
such as the Arctic Oscillation and the Madden-Julian Oscillation. Just more
to talk about in future Franklin Facts.