What is thermal pollution and what are its causes

We can define thermal pollution in a more colloquial way as a process that modifies the temperature of the environment in a harmful way . This modification can be both a rise and a drop in temperature, which can negatively affect the quality of air, water and also living beings.

It is more common for thermal pollution to manifest itself in the aquatic environment, because in the air this type of pollution can disperse more quickly. Although, it is not exempt from suffering it, for example, through air conditioners that emit heat to the street.

In addition, the high thermal inertia of water makes it an ideal element to store heat. This fact is used by thermal power plants, since they do not convert all the chemical energy into electricity and release the rest in the form of heat, so they need a cooling system. However, before throwing this water at high temperatures into rivers and seas, they pass it through an evaporation tower that reduces part of this temperature. This process alters some of the physicochemical characteristics of the water of rivers and seas. For this reason, the power plants are located near rivers and seas.

In fact, as we can see in this other AgroCorrn article, thermal power plants are one of the most polluting power plants .

Among the main causes of thermal pollution we find the following:

Use of water as a cooling system

The main cause of thermal pollution due to this factor is industrial and manufacturing plants. These plants obtain their water from nearby sources to avoid excessive heating of their machines, which they then pour back to this source but at a higher temperature. When this water is returned to its natural source, the temperature of that body of water increases significantly. This has as a consequence a decrease in oxygen levels, a decrease in the longevity of marine organisms, loss of vegetation or destruction of marine habitats.

Soil erosion

Erosion in the soil leaves the bodies of water more exposed to the heating of the sun. This leads to damage to the aquatic biomes, as it favors anaerobic conditions in these places. Furthermore, soil erosion has many more negative consequences.

Deforestation

Vegetation also acts as an impediment for solar energy to reach ponds, rivers and lakes directly. When there is a deforestation process, the elimination of plants and trees allows the bodies of water to absorb more heat from solar energy. Deforestation is also one of the most important causes of increases in greenhouse gas concentrations. Learn in this other article all about the Causes of deforestation , as well as its consequences, including this one, and possible solutions.

Runoff from paved surfaces

During the summer season, the pavement overheats, creating hot water runoff into sewer systems and other surface waters.

Natural causes

Among these causes, we find volcanoes and geothermal activity at the bottom of the oceans and seas and that can cause lava to heat bodies of water. We also find solar rays, which introduce a large amount of heat into the oceans.

Finally, we reflect on the consequences of temperature or thermal pollution. Thus, among the negative effects of thermal pollution are:

• Reduction in dissolved oxygen levels: hot water retains less oxygen than cold water. This drop in oxygen levels can suffocate plants, amphibians, copepods or fish, causing loss of marine biodiversity . In addition, this warm water allows the growth of algae on the surface, which prevents the passage of oxygen and sunlight to the seabed.
• Increase of toxins: the water of the industries that flows towards seas and rivers, can contain toxins. These toxins can have a negative effect on the ecology of the area, causing more diseases to develop.
• It affects the reproductive system: high temperatures can prevent reproduction in some species, contributing to the loss of biodiversity. Sometimes, although they do not prevent reproduction, they can cause newborn malformations or premature mortality.
• Increases metabolic rate: high temperatures can increase the metabolic rates of species, causing them to consume more food. In turn, this upsets the stability and balance of the food chain.
• Migration: the increase or decrease in temperatures can cause species to migrate to environments where the conditions are more suitable, affecting organisms that depend on these species for their survival.

Here you can find out more about The environmental impact of rising temperatures .

If you want to read more articles similar to What is thermal pollution and what are its causes , we recommend that you enter our Pollution category .