For example, the 1997 El Ni o that boosted global temperatures to record highs was unanticipated, as was its intensity. But once one of the conditions settles into place, meteorologists have become adept at predicting the consequences and incorporating those patterns into long-term forecasts. Fahrenheit through the course of a year. El Ni o can raise surface temperatures 14 degrees above normal over an area three times the size of the contiguous United States. La Ni a can drop it nearly 8 degrees.
More heat causes more evaporation and more rising hot air, meaning more storms.
El Ni o has been linked to strong winter storms that batter Southern California, to a weak hurricane season in the Atlantic as high-altitude winds shear the towering tops from developing tropical storms, to searing droughts in southern Asia like the one that spawned enormous rain forest fires in Indonesia in 1997. La Ni a, among other things, seems to nurture Atlantic hurricanes, push the North American winter storm track further north, and bring heat and drought to the West. Without either, weather becomes typical meaning largely unpredictable meteorologists say. Precipitation charts are a little less equivocal, but only a little. He said meteorologists, if they are prudent, will probably include strong caveats in any long-term forecasts in the coming months.