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WEATHER
Lesson 2 - Page 3

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The biological community that lives in the eastern Pacific Ocean likes cold water, which come from the bottom waters and surfaces (called upwelling) along South America and the North American west-central coast. Water upwells because the wind blows seaward, causing the water to move westward. This leaves a water "gap" which must be replenished. Cold water that circulates on the bottom, moves upward bringing cold water. This cold water brings nutrients such as oxygen, nitrates, phosphates, and silicates that are essential to the growth of little organisms called plankton, which is food for bigger animals.

These little organisms, many no larger than the diameter of your eyelash, begin what is called the food chain. Little plants (mainly diatoms) are eaten by larger critters (foraminifera, radiolarians, and other one celled protozoa) which in turn are eaten by larger organisms (copepods, krill) which is the main staple of fish which in turn serve as food for the very large fish, marine mammals, and marine birds. When the little plants cannot convert sunlight to useable energy, the other organisms in the food chain have little available food. The links in the chain are broken, only to cause starvation and death affecting even the largest organism in the food chain.

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