4.9 El Nino and La Nina

Question 1

El Nino

Answer 1

trade wind crossing the Pacific is weaker than normal, which results in less upwelling of cold water in the east. This means that fewer nutrients are available for fish and pushes rainfall further out to sea.

Question 2

During an El Nino, which countries experience more rainfall than usual? Which ones experience less rainfall than usual?

Answer 2

Peru and the southern US experience more rainfall; Australia and Indonesia experience less rainfall

Question 3

In an El Nino, global temperatures are…?

Answer 3

usually warmer than usual

Question 4

La Nina

Answer 4

trade winds crossing the Pacific are stronger than normal which results in more upwelling of cold water in the east. This means more nutrients are available for fish. This pushes rainfall further inland out to sea

Question 5

During a La Nina, which countries typically get less rainfall than usual?

Answer 5

Peru and Southern US

Question 6

During a La Nina, which countries experience more rainfall than usual?

Answer 6

Australia and Indonesia

Question 7

During a La Nina, global temperatures are…?

Answer 7

cooler than usual

Question 8

upwelling

Answer 8

horizontal surface currents diverge from one another, cold and deep waters are pulled to the surface; sites of high primary productivity, upwelled water is rich in nutrients

Question 9

downwelling

Answer 9

surface currents converse and transport warm surface water (rich in dissolved gases) to deeper waters