Particulate Matter Pollution Status In Karachi
By: Areesha Muntaha
Air Pollution In Developing Countries
Air pollution is among the greatest concerns in the present time threatening the sustainability of developing countries. Enhancement in urban expansion in developing countries is acting as a catalyst for increased pollution load and climate change. Due to urban expansion, the population in the cities is also increasing which in turn causes the elevation in vehicular traffic which serves as the major route of air pollution in the cities. The increase in urban population and developed industrialization is a major source of air pollution in Karachi, Pakistan.
Major Air Pollutants
Air pollution can come from various sources, and it may constituent of several types of secondary and primary pollutants. Primary pollutants are those which enter the environment directly from the source including suspended particles, CO, SOX, NOx, ammonia, dust particles, and particulate matter. Whereas secondary pollutants are formed when primary pollutants react in the atmosphere including smog, PANs (Per-oxyacetyl nitrates), ozone, etc.
Air Pollution In Karachi
The air quality index of Karachi stands at 190 on Friday 22 June 2022, which is 13.2 times higher than the permissible limits provided by the WHO and it is expected to increase further in the coming week. An AQI less than 50 shows that the sir is safe but an AQI level ranging more than 100 poses a great threat to the unhealthy individuals suffering from heart and lung diseases as well as is harmful to children.
The main pollutant contributing to Karachi’s air pollution is a particulate matter more specifically PM 2.5. PM is defined by its size rather than the chemicals in it as PM 2.5 is any particle (liquid or solid) size 2.5 micrometers similarly PM 10 is any particle whose size is 10 micrometers. PM 2.5 are small inhalable particles with diameters thinner than a human hair. These can penetrate the lung barrier entering the bloodstream and cause health damage at a micro-level. There are several sources of PM 2.5 in the atmosphere including industrial emissions and combustion primarily from the fireplaces, engines, and gas-fired powered plants into the atmosphere.
Dispersion of Air Pollutants In Karachi
Climate has a significant impact on the geographical and temporal distribution of air pollution. Greenhouse warming and stratospheric ozone depletion are important drivers of climate change. Climate change can affect air pollutant concentrations and promote secondary pollutant generation. In addition to atmospheric characteristics, terrain and urban settlements all have an impact on the dispersion, accumulation, and transformation of pollutants in the atmosphere. South westerly winds in Karachi help in the dispersion of pollutants in summers whereas in winters winds travel from the north-eastern direction and it is not favorable for the dispersion of pollutants thus the pollution levels are higher in Karachi during winters than the summers.
How To Reduce PM
Particulate matter comes from various sources, and it is not possible to completely end particulate matter from the atmosphere, but it can be controlled. Karachi has high vehicular traffic, and a substantial portion of particulate matter comes from the burning of fossil fuels. Lesser number of vehicles might help in reducing particulate matter i.e., a mass transit system helps combat pm pollution. Similarly, avoid open burning of waste and stay indoors to avoid elevated levels of particulate matter pollution.