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.