Question

Thermal pollution, is more prevalent near
A) Hot water springs
B) Coal Based power plants
C) Temperate zones
D) Tropical zones

Answer 1

Introduction of contaminants into the natural environment that cause adverse change is known as pollution.The word thermal comes from the Greek word “therm” meaning heat.

Complete answer:
Thermal pollution is any deviation from the natural temperature in a habitat and can range from elevated temperatures associated with the industrial cooling activities to discharges of cold water into streams below large impoundments.
It is also related with the degradation of water quality by any process that changes the ambient water temperature. Heat is classified as a water pollutant when it is caused by heated industrial effluents or from man-made changes of stream bank vegetation that increase the water system temperatures due to solar radiation. A common cause of thermal pollution is the use of water as a coolant by power plants and industrial manufacturers.
Heated discharges into a stream or lake may change the ecology of the water system. Although heating limited to a single small place (localised) can have beneficial effects like freeing harbours from ice, the ecological effects are harmful. Heat also increases the metabolic rate of aquatic organisms which further reduces the amount of dissolved oxygen because respiration increases. Extreme heated temperature can also result in the death of the organism. Heated water when released lowers the solubility of oxygen in the water because gas solubility in water is inversely proportional to temperature and thus it reduces the amount of dissolved oxygen available to aerobic species.

Thus, the correct answer is option B (Coal based power plants).

Note: Some of the other important sources of thermal pollution are nuclear power and electric power plants, crude oil refineries, steel melting factories, coal fired power plants, boilers from industries.