ocean current
El Nino has been a reoccurring phenomenon for centuries. Man has only started to realize how much of the worlds weather is effected by it. The term El Nino refers to an irregular warming of the seas surface. During the last 40 years there have been 10 significant El Nino occurrences. Most affecting the coast of South America. Water temperatures increase along the coast as far as the Galapagos islands. Weak events will raise the water temperature 2 to 4 degrees Celsius and will have minor impact on fishing. However strong events such as the 1982-83 event will disrupt climate conditions around the world as well as local conditions. It has been linked to floods and droughts all over the world. Hurricanes and tropical storms are also altered in their numbers by El Nino. Therefore it would be very helpful for people if El Nino could be predicted and prepared for in some form. During a El Nino cycle there are many biological changes. Due to a depressed thermocline there is less photosynthetic activity resulting in a decrease in the primary life forms that form the beginning of the food chain. The warmer waters that are brought by these changing cycles hold less dissolved oxygen forcing fish to go deeper or venture
sappear during low index years, but east of the dateline they only weaken. The surface winds that move the ocean currents are a major controller in weather. The easterly winds that blow along the Ecuador and the southeasterly winds that blow along the Peru and Ecuador coasts both tend to drag surface water with them. The Earth's rotation then deflects the resulting surface currents northward in the Northern Hemisphere and southward in the Southern Atmosphere. The surface waters are therefore deflected away from the equator in both directions and away from the coastline. When the surface water moves away, colder nutrient-rich water comes up from below to replace it. This is known as upwelling. This nutrient rich water is the beginning of the food chain as phytoplankton establish themselves in these waters. Scientists noticed that a monsoon season with low index conditions are often marked by droughts in Australia, India, Indonesia and parts of Asia. Although scientists did not realize the magnitude of what they were discovering they knew they had discovered only a small portion of this phenomenon. It would require a knowledge of wind patters above ground level (which were not recorded at that time) to continue to gain knowledge. In the following decades researchers added new pieces to the emerging picture of Southern Oscillation. When the easterlies are blowing at full strength, the upwelling of cold water along the equatorial Pacific chills the air above it, making it too dense to rise high enough for water vapor to condense and form clouds. As a result, this strip of ocean stays free of clouds during normal years and rain in the equatorial belt is largely confined to the extreme western Pacific near Indonesia.
Some common words found in the essay are:
El Nino, Equador Peru, Southern Atmosphere, America Water, Southern Oscillation, Pacific West, Indonesia Australia, Indonesia Asia, el nino, Hawaii Tahiti, EL Ninos, western pacific, surface winds, low index, wintertime el nino, el nino event, wintertime el, easterly surface, nino occurrences, winds blow, surface water, beginning food, easterly surface winds, el nino occurrences, beginning food chain,
Approximate Word count = 1432
Approximate Pages = 6 (250 words per page double spaced)
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