What is Air Pollution? * Air pollution can be defined as the presence of any harmful material in the air and the atmosphere that can cause damage to human beings and other living organisms. * Air pollution could also be in the form of disturbances to the normal composition of the air such that there is an undesired effect on the environment or living things. * Under normal circumstances, the earth’s atmosphere consists of nitrogen (~78%), oxygen (~21%), small amounts of carbon dioxide (~0.03%) and other gases like water vapor and some tiny particles of liquid/solid matter like dust.
Natural Sources of Air Pollution
A. Volcanic Eruptions * Carbon dioxide and sulfur dioxide are the primary gases that are released during volcanic eruptions. * Other gases like hydrogen sulfide, hydrogen chloride, hydrogen fluoride, carbon monoxide, halocarbons and some metal chlorides are also released into the atmosphere. * Besides the volcanic gases, there is also volcanic ash. Volcanic ash can move hundreds to thousands of miles downwind from a volcano.
B. Forest Fires * All forest fires emit carbon monoxide, sulfur dioxide, nitrogen dioxide, ozone, and particulate matter.
C. Wind Erosion * Acts by picking up loose particles of dirt and soil, mostly where plants are too sparse to hold the soil together.
D. Radon Expulsion * Nuclear elements like uranium are found inside the earth’s surface, and when these elements decompose they release a noble gas known as Radon into the atmosphere.
E. Methane Expulsion * Farm animals like cattle release methane into the atmosphere during the end stages of their digestive cycles. * Methane is also produced by the natural rotting of plants.
Factors Affecting Air Quality such as
Weather, Wind and Geography
* Turbulence mixes pollutants into the surrounding air.
* Wind speed also contributes to how quickly pollutants are carried away from their original