The climate phenomenon El Ni単o is likely to return this spring, say US climate scientists, but it is too early to predict its impact or how long it could last.
“The magnitude of an El Ni単o determines the severity of its impacts,” says Vernon Kousky of the US National Oceanic and Atmospheric Administration. “At this point, it is too early to predict if this El Ni単o might develop along the same lines as the 1997-8 episode, or be weaker.”
El Ni単o occurs every two to seven years, when cold water in the eastern Pacific around Ecuador and Peru becomes unusually warm. This can trigger a switch in weather patterns, with potentially disastrous consequences.
The last El Ni単o caused extensive flooding in Peru and Ecuador and droughts in Papua New Guinea, the Philippines and Indonesia. Severe winter storms hit Chile and California.
Advertisement
Clouds gathering
NOAA researchers say they have identified higher than normal levels of cloud and precipitation over the equatorial central Pacific for the first time since the last El Ni単o. Researchers say they should have a clearer idea of whether an El Ni単o will develop and what its impact might be within the next few months.
“The first region on the globe to experience El Ni単o’s impacts would be in the tropical Pacific,” says Kousky. “Indonesia is likely to get some relief from torrential rains. If El Ni単o develops as is presently indicated, the Pacific northwest will experience wetter than normal conditions this fall.”
“In the US winter,” he adds, “Louisiana eastward to Florida, and possibly southern California, could also experience wetter than normal conditions, and the northern Great Plains will experience warmer than normal conditions.”
NOAA hopes long-range forecasts of El Ni単os like these will help save lives and property. The agency says preparations made in California after advanced warning of the last El Ni単o reduced losses during the storms by about $1 billion.
