A massive pool of warm ocean water is causing changes in the atmosphere that could produce unusual weather around ihc world in the next few months. the US National Weather Service reported on Monday. As a result of this phenomenon. known as El Nino, more rainfall than normal is likely this winter across some areas of the United States, with unusually warm or cold weather in other parts of the country. Currently the phenomenon is marked by a warm pool of water along the equator extending from the International Date Line nearly to the coast of South America. That water is nearly 4. degrees Fahrenheit above normal. explained Vernon Kousky of the climate center. This warm water "spreads almost a quarter of the way around the globe. So it's massive and it has an impact on our weather. It has a global influence... because it disturbs the atmosphere", said Dave Rodenhuis. director of the climate center. "E1 Nino is probably the most important climate event beyond the annual cycle of seasons", he added. Because the changes tended to be first noticed around Christmas, the phenomenon was given che name El Nino, which is Spanish for child, a term often used to refer to the baby Jesus. The phenomenon occurs every three to five years, sometimes in a mild form and sometimes strongly affecting weather patterns worldwide. Details of its cause are not fully understood, but when it occurs. unusually warm air can be pumped into Canada. Alaska and the northern United States. At the same time, conditions tend to be wetter than normal along the US Southeast Coast and the Gulf of Mexico. And the Atlantic and Caribbean hurricane season tends to be milder than usual. The strong El Nino of 1982-1983 was blamed for worsening the devastating drought in Africa, causing a series or severe winter storms to come ashore in California, spawning the first typhoon to strike French Polynesia m 75 years-followed by five more in Five months-deluging Peru and Ecuador with torrential rains and promoting the worst drought in two centuries in Australia. Overall damage was estimated at between $2 billion and $8 billion by a United Nations analysis and the death toll topped l,500 worldwide.