9/18: Practice Question #1

a) Shutting down thermohaline circulation would lower the temperature of Western Europe because the salt water in the oceanic region may not be dense in salinity. Thermohaline circulation drives the mixing of surface water and deep water; the supposedly dense, cold, salty water from the poles would sink, allowing warm water from the equator to rise, but if the water from Greenland is not dense enough, then the warm water's rising to Western Europe may not be guaranteed, resulting in a decreased temperature in Western Europe.

b) There would be large populations of fish along the west coasts of most continents because of the upwelling caused by the diverging currents. Upwelling is the rise of ocean water toward its surface, and because deep waters bring nutrients from the bottom, the ecosystem is more productive, allowing large populations of fish to reside.

c) Shutting down thermohaline circulation would affect the transport of nutrients among the oceans of the world because the mixing of surface water and deep water would be prevented, and as a result, the nutrients from the bottom of the ocean would not be transferred to the surface. The diverging currents, then, would not be able to circulate water containing nutrients, which would have been present if the thermohaline circulation were active.