El Nino is Spanish for "the boy," but that's probaly not what your looking for. El nino is the name given to the supposed change in the earth's climate from cold to warmer a few years ago. Don't worry too much about this. A few years after el nino, many "scientists" suddenly changed their minds and told us to worry about La nina (the girl) saying that the earth's cimate is getting colder. All el nino is, is the overall benign fluctuation of climate the earth had from cold to warm. Many people contribute green-house gases (a car's exhaust, wood or coal fires, cows passing gas, etc.) to El nino, but the threat is somewhat exaggerrated. As long as we keep harmfull gases and other toxins relatively in check (I don't know what to do with those cows), we should be just fine.

Okay, first note that I have not consulted any dictionary or educational references to El Nino previous to writing this message (I am too lazy for that), I am only using stuff I remember from a long while ago. El Nino is a catastrophic shift in ocean currents in the central Pacific Ocean. Normally, cold water from the deep surfaces near South America and flows West and to near Australia, warming along the way. Here is descends to near the ocean floor to cool and travel back to South America. During a period of El Nino (which I believe is a periodic event and not just a single event in history), the current is reversed (for all intents and purposes, anyway). This brings warm water to South America's shallows, and cold water to Australia's shallows. This kills many species of Fish which are sensitive to temeperature, but it also affects mineral content of the water - the warmer water is generally more stagnant, and the cold water from the deep is rich in minerals and nutrients from the detritus and debris on the ocean floor. The change in currents also affects wind direction, but more importantly global weather patterns. Having warm water surface near South America's West side increases upward moving moist air, where normally there would be downward moving dry air. In the last few years, we have had an unusual El Nino cycle that affected the ocean currents near North America. As a consequence, the world has seen particularly unusual weather patterns. La Nina is (for all intents and purposes) the REVERSAL of El Nino - as in, the return to normal. During this transition period (where the ocean currents are in a state of confusion), we see even wierder weather patterns. Whales get lost, dolphins die of starvation, fish die from all sorts of things ... etc etc. Global warming is a generally unrelated issue - although there can be some ties hypothesized by energy transfer from the earth to the atmosphere during the changes. There is evidence indicating that the global warming we are experience may actually be part of a larger natural cycle (Ice Core samples from antarctica indicate the planet goes through warming and cooling cycles over a very long period of time). Cheers! hope this helps. Hope I am right LOL!

Simply put, El Nino, or ENSO (El Nino Southern Oscillation) is a shift in the temperature and current pattern of the ocean and the pressure pattern of the atmosphere along the equatorial Pacific Ocean. There is usually cold water off the west coast of South America, due to a cold ocean current, and upwelling which is prominent, bringing cold water and nutrients to the surface. Also during normal conditions, there is a general area of atmospheric surface high pressure over this area, and an ocean current flowing from east to west along the equator. During an El Nino, this area experiences a warming of the water off the S. American west coast, and a drop in surface pressure, and as a result, more precipitation. Likewise, during an El Nino in the equatorial western Pacific, the usual warm water temperatures cool, and an anomalous higher atmospheric pressure is present. It is not known at this time as a certainty what is the root cause of this fluctuation, i.e. whether the change in ocean currents drive the atmospheric changes, or the atmospheric changes drive the ocean currents. Likely, since the ocean has so much inertia, it is caused by a change in oceanic temperature and circulation. This has been happening for as long as we can measure, though periods with stronger El Nino's have occurred, especially in the last 20 years. El Nino is not blamed for or the cause of any drastic long-term global climate change, such as Earth warming or cooling climatologically, i.e. global warming or an ice age. It has been demonstrated that changes due to El Nino affect the weather (not the Earth's climate), in the Pacific and North America. For example, due to research results, it is believed that during strong El Nino winters, the US Gulf Coast experiences more precipitation than climatologically normal. There are several other areas of the country that experience change in winter climate due to El Nino as well. More work is ongoing to assess the affect of El Nino on Earth's weather.

El Niño is the warming of the surface waters of the eastern equatorial Pacific Ocean that occurs at irregular intervals of 2-7 years, usually lasting 1-2 years. Along the west coast of South America near the end of each calendar year, a warm current of nutrient-poor tropical water replaces the cold, nutrient-rich surface water of the Humboldt Current which fish prefer. El Niño was originally recognized by fishermen off the coast of South America (Peru and Ecuador) as the appearance of unusually warm water in the Pacific Ocean. Because this condition often occurs around Christmas, local fishermen named it El Niño (Spanish for boy child, referring to the Child Jesus). In most years the warming lasts only a few weeks or a month, after which the weather patterns return to normal and fishing improves. However, when El Niño conditions last for many months, more extensive ocean warming occurs and economic results can be disastrous. El Niño's weather effects depend on the location, time of year, and the particular episode. In North America, typically, winters are warmer than normal in the upper midwest states and Canada, while central and southern California, northwest Mexico and the southeastern U.S., are wetter than normal. The Pacific Northwest states, on the other hand, tend to be drier during an El Niño. During a La Niña, by contrast, the midwestern U.S. tends to be drier than normal. In South America, the effects of El Niño are rather direct and stronger than in North America. An El Niño is associated with very wet summers in the coasts of Northern Peru and Ecuador causing major flooding whenever the event is strong or extreme. The effects during the months of February, March and April may become critical. Central Chile receives large rainfall during winter, and the Peruvian-Bolivian Altiplano is sometimes exposed to unusual winter snowfall events. The entire peruvian coast and parts of northern Chile experience above-normal temperatures and moist conditions for several consecutive months as well. Drier and hotter weather occurs in parts the Amazon River Basin, Colombia and Central America. Australia and Indonesia experience as well direct effects of El Niño resulting in drier conditions. Africa experiences droughts both in northwest Africa and in south-central Africa. http://www.answers.com/el+nino