Hyderabad: The rise in ground-level ozone gas during the summer season this year has made the air toxic in Hyderabad.
As per the study conducted by the Centre for Science and Environment (CSE), Delhi-NCR, Mumbai, Kolkata, Hyderabad, Chennai and Bengaluru have witnessed ‘ozone-exceedance’, a phenomenon wherein the ozone concentration at ground-level increase above normal level. The assessment was made during summer between March 2019 and May 2022.
While Delhi-NCR recorded ozone-exceedance on all the days of summer whereas, Chennai and Bengaluru recorded longer duration of the phenomenon. Mumbai and Kolkata saw ozone-exceedance on 75 and 43 days respectively.
In Hyderabad, ozone-exceedance was recorded on 43 days of the summer as the temperature in the city has breached 40 degrees Celsius-mark multiple times in the current summer season.
What is ground-level ozone?
It is a gas which is also referred as surface-level ozone.
Although, it is least concentrated in the ground level, it increased due to chemical reaction between nitrogen oxides, which is produced due to combustion, and volatile organic compounds in the presence of sunlight.
As ground-level ozone is one of the greenhouse gases, it contributes to the global warming.
Is it harmful for health?
Ozone at stratospheric level protect the earth from harmful UV radiation from the Sun. However, the same gas at the tropospheric level is harmful for the health.
Some of the health issues due to the increase in the concentration of ground-level ozone are
- Respiratory issues
- Breathing issues
- Aggravation of asthma etc.
As high temperature is needed for the photochemical reaction for the formation of ground-level ozone, its concentration increases during summer season.
As this summer was the hottest season in the India’s history, the concentration of ground-level ozone increased in Hyderabad and other metro cities of the country.
