Particulate matter Current Affairs - 2020

NASA: Air Pollution in India at 20 year low

On April 22, 2020, NASA (National Aeronautics and Space Administration) announced that Air Pollution in India has reached 20 year low.


According to the data published by NASA, the Aerosol Optical Depth in 2020 has been the least as compared to the average of 2016 to 2019. Aerosol Optical Depth is absorption of light by airborne particles in the atmosphere. When the aerosols are near the surface, the optical depth of 1 or above indicate hazy conditions.

The AOD was 0.7 in 2016 and has now reached 0.1. The patterns were observed by the MODIS model. MODIS is Moderate Resolution Imaging Spectroradiometer

Aerosol Optical Depth

The aerosols are particles in atmosphere released due to anthropogenic activities such as industries, vehicles and natural events such as dust storms, fires, etc. The presence of Aerosols in the atmosphere is also affected by particulate matter in the atmosphere.

The Aerosol Optical Depth is the quantitative measure of aerosols present in the atmosphere. It measures the extinction of light when it passes through the atmosphere. As AOD increases, the rate of extinction of light increases.

SC issues order on completion of “Smog Tower Project” within 3 months

On December 16, 2019, the Supreme Court of India ordered the Centre and the Delhi Governments to hasten the pilot project of setting up smog towers at Connaught place.

Smog Towers

Smog Towers are air purification structures that are designed to work as air purifiers. They are fitted with multiple air purifiers. These purifiers cleanses air as it passes through them. It is a successful project and China has fitted two smog towers in the city of Beijing and Xi’an. The tower is being developed in Delhi by Kurin systems called the “Kurin Cleaners”

About the towers

The purifiers will be 20-feet wide and 40-feet tall. They will have the capacity to clean 32 million cubic metres of air in a day. A single tower will cover 3-km radius and is said have impacts on 75,000 lives of Delhiites.

The Kurin cleaner will remove PM 10 and PM 2.5 upto 99.99%. It will run on solar energy. As many as 48 fans will be fitted to these towers to maintain air flow. The towers will also be attached with solar heating and cooling techniques.