what is el nino and what are its affects on an area?

Answer 1

Background:

El Niño-Southern Oscillation (ENSO) is a global coupled ocean-atmosphere phenomenon. The Pacific ocean signatures, El Niño and La Niña (also written in English as El Nino and La Nina) are major temperature fluctuations in surface waters of the tropical Eastern Pacific Ocean. Their effect on climate in the southern hemisphere is profound. These effects were first described in 1923 by Sir Gilbert Thomas Walker from whom the Walker circulation, an important aspect of the Pacific ENSO phenomenon, takes its name. The atmospheric signature, the Southern Oscillation (SO) reflects the monthly or seasonal fluctuations in the air pressure difference between Tahiti and Darwin. As of September 2006, El Niño is currently active, and has continued into 2007.

What it is:

El Niño/Southern Oscillation (ENSO) - A shift in the normal relationship between the atmosphere and ocean in the tropical Pacific Ocean. Normally, strong winds (called trade winds because they aided sailing ships transporting goods) blow to the west in the Pacific, moving warmer surface water away from North and South America. Simultaneously, cold water from the ocean depths rises to the surface off the west coast of South America. This upwelling brings nutrients to the surface, supporting fisheries and ecosystems in the area. In an El Niño event, these trade winds die down, causing warmer surface water to accumulate off western North and South America. This leads to increased rainfall, storm activity, and flooding in the Americas (especially the southwestern United States and Peru) and drought conditions in Australia and other areas in the western Pacific and the Indian Ocean. Fisheries on the west coasts of North and South America are also seriously affected.

Effects in South America:

In South America, the effects of El Niño are direct and stronger than in North America. An El Niño is associated with warm and very wet summers (December-February) along 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. Southern Brazil and northern Argentina also experience wetter than normal conditions but mainly during the spring and early summer. Central Chile receives a mild winter with large rainfall, and the Peruvian-Bolivian Altiplano is sometimes exposed to unusual winter snowfall events. Drier and hotter weather occurs in parts of the Amazon River Basin, Colombia and Central America.

Effects in North America:

In North America, typically, winters are warmer than normal in the upper Midwest states, the Northeast, and Canada, while central and southern California, northwest Mexico and the southwestern U.S., are wetter and cooler than normal. Summer is wetter in the intermountain regions of the U.S. The Pacific Northwest states, on the other hand, tend to experience dry but foggy winters and warm, sunny and precocious springs during an El Niño. During a La Niña, by contrast, the Midwestern U.S. tends to be drier than normal. El Niño is associated with decreased hurricane activity in the Atlantic, especially south of 25º N; this reduction is largely due to stronger wind shear over the tropics.

Answer 2

A major warming of the equatorial waters in the Pacific Ocean. El Nino events usually occur every 3 to 7 years, and are characterized by shifts in "normal" weather patterns.

When In Doubt Google!

Answer 3

Actually, a complicated question.... the prevailing winds in the northern hemisphere travel from west to east. Weather systems follow this pattern, of course. El Nino describes a very broad ocean current of warm water in the Pacific. If it shifts even a little north of its usual west - east flow, it brings warmer waters northward. The prevailing wind, traveling over this warmer water, bring warmer air farther north into North America than usual, upsetting weather patterns. The results make the west coast warmer and generally cause cold Arctic air to plunge further southeast into central/eastern US and Canada... layman's terms!!

Answer 4

el nino is a weather term.El nino is a disruption of the ocean-atmosphere system in the Tropical Pacific having important consequences for weather and climate around the globe

Answer 5

Depends on the area...

Heightened (and more severe) storms, drought, heat waves, heavy snow, etc.

El nino currents only last a few months, but have global effects for a year or more.

As for what it is, it is an upwelling of war water off Peru.

Answer 6

Not likely.