Air and Noise Pollution: Causes, Effects, and Solutions
What is Air Pollution?
Air pollution is the release into the air of substances in solid, liquid, or gas form, or energy (heat, noise, radiation), altering its natural composition and posing risks, harm, or serious problems to people, ecosystems, and property of any nature.
Understanding Smog Formation
Smog forms due to the concentration of air pollutants released primarily in metropolitan areas by industrial activities, heating, and traffic. In the accompanying drawing, the source of the smog is mainly attributed to the first two activities, resulting in a composition based on sulfur oxides (acid smog or classic smog). The formation of this smog is favored by anticyclonic situations or atmospheric stability, the absence of winds, and the location of cities in depressions or valleys. Furthermore, this concentration of pollutants is amplified during temperature inversions because the lack of vertical dispersion causes pollutants to become increasingly concentrated, increasing the density of the contaminated layer and fueling the process.
Climatic Conditions and Air Pollutant Dispersion
The degree of dispersion achieved when gaseous pollutants are released into the atmosphere depends on several factors, one of the most important being weather conditions. Anticyclonic conditions lead to stability, causing gaseous pollutants to concentrate. Conversely, storms facilitate the dispersion of pollutants. If a temperature inversion does not occur, the vertical dispersion of air pollutants is hindered, causing them to accumulate between the surface and the base of the inversion layer. Winds, whether regional, such as gales, or local, such as mountain-valley and sea-land breezes, also affect the dispersion of air pollutants.
Ozone: Definition and Atmospheric Function
The ozone layer forms in the stratosphere, where solar radiation electrically excites atoms and molecules of atmospheric gases, including oxygen, which dissociates to form ozone. The ozone layer absorbs ultraviolet radiation from the sun, consequently protecting life on Earth’s surface.
The Greenhouse Effect and the Kyoto Protocol
The release of greenhouse gases (CO2, CH4, N2O, CFCs) into the atmosphere enhances the absorption of heat rays or infrared rays emitted by the Earth’s surface, known as contraradiation. The immediate consequence is the greenhouse effect, contributing to an overall increase in global temperature. An increase of 2 to 3 degrees Celsius in global temperature could cause the melting of polar ice, leading to a rise in sea levels and flooding of many densely populated coastal areas. Moreover, there would be changes in climate, with unpredictable consequences for ecosystems and humanity. The Kyoto Protocol, established in 1997, proposed a global strategy to reduce greenhouse gas emissions. Ultimately, 159 countries reached the first concrete commitment: an overall reduction by industrialized countries of 5.2% in the emissions of six greenhouse gases: carbon dioxide, methane, nitrous oxide, hydrofluorocarbon, perfluorocarbons, and sulfur hexafluoride.
Noise Pollution: Concept and Effects
Noise pollution is defined as any unwanted sound that disrupts, injures, or interferes with the hearing or well-being of people. Its effects on human health, especially when exceeding 75-80 dB, can be:
- Psychological: stress, insomnia, irritability, etc.
- Physiological: partial or total hearing loss, changes in blood pressure, abnormal hormonal secretion, migraines, etc.