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Which of the following best describes the effects of a thermal inversion?
a) Cold ocean water moves to the surface and warm water sinks.
b) Warm, polluted air rises and mixes with cool upper air, and pollutants escape.
c) Warm river water cools when it enters the ocean.
d) Warm, polluted air cannot rise because it is blocked by warm air high in the atmosphere.
e) Cool air descends onto a city and lowers nighttime temperatures.
What is (d) Thermal inversions occur when a warm layer of air prevents polluted air from rising up over a city. Normally, cool upper air allows the warm air to rise, and the pollutants are dispersed along with the warm air. When an inversion occurs, the upper air is warmer and the polluted air cannot rise.