Upwelling：练习题

What is the primary biological reason why regions of upwelling have high levels of marine productivity?

What is the primary physical process that causes upwelling, where nutrient-rich, cold water rises to the surface, supporting high productivity?

How does the deepening of the thermocline in the eastern Pacific during an El Niño event affect the process of upwelling?

During an El Niño year, what change typically occurs to the surface water temperature in the eastern Pacific Ocean compared to a normal year?

In an area of coastal upwelling, winds move surface water away from the shore. Which statement best explains why the water rising from the depths to replace it is specifically nutrient-rich?

State the effect of upwelling on the temperature of the surface water in the region where it occurs.

Describe the relationship between trade winds and the movement of warm surface water in the eastern Pacific during an El Niño year.

Explain how the reduction of trade winds during an El Niño event leads to a deepening of the thermocline and describe the resulting impact on the vertical transport of nutrients and coastal productivity in the eastern Pacific.

(a) Define the term upwelling.
(b) Identify two physical or chemical characteristics of the water that is brought to the ocean surface during an upwelling event.
(c) State why regions of the ocean where upwelling occurs often support very large populations of fish.

The El Niño-Southern Oscillation (ENSO) significantly alters upwelling patterns in the Pacific Ocean.
(a) Outline how the trade winds change during the formation of an El Niño event.
(b) Explain why the surface water temperature in the eastern Pacific increases when upwelling is reduced.
(c) Contrast the typical rainfall levels in Australia during an El Niño year with those of a normal year.