Understanding El Niño and La Niña

What causes the tropical oceans to be warmer than other parts of the world?

• The poles receive more solar radiation per unit area.

• The wind patterns are more stable at the equator.

• The ocean currents are stronger at the equator.

• The equator receives more solar radiation per unit area.

What is the term used to describe the sharp change in temperature below the ocean surface?

• Temperature gradient

• Thermal layer

• Isotherm

• Thermocline

How often does the warm pool of water spread eastward during El Niño?

• Every 20 years

• Every year

• Every 10 to 15 years

• Every 2 to 7 years

What does a positive Nino 3.4 index indicate?

• Development of La Niña

• Increased biological productivity

• Development of El Niño

• Normal sea surface temperatures

What happens to the sea level during La Niña?

• It is generally higher than normal.

• It is generally lower than normal.

• It remains unchanged.

• It fluctuates unpredictably.

What is the Walker Circulation driven by?

• Trade winds

• Atmospheric convection over warm waters

• Solar radiation

• Ocean currents

During La Niña, which region experiences wetter than normal conditions?

• Southern Brazil

• Northern Brazil

• Central America

• Equatorial East Africa

What effect does El Niño have on the maritime continent?

• It becomes drier than normal.

• It becomes wetter than normal.

• It experiences increased biological productivity.

• It experiences no change.

What happens to the biological productivity off the coast of Peru during La Niña?

• It remains constant.

• It decreases due to warmer waters.

• It increases due to upwelling of cold water.

• It fluctuates unpredictably.

How can studying ENSO events help us?

• By controlling the weather patterns.

• By making better predictions of the climate system.

• By reducing global warming.

• By increasing fish populations.