In a recent study conducted by the Indian Institute of Tropical Meteorology (IITM), Pune, it was discovered that pollutants originating from South Asian nations can heighten the impact of climate cycles such as El Nino on the monsoon, thereby contributing to increased drought severity in India. The research provides insights into the profound influence of aerosol pollution loading over South Asia on weather patterns and suggests potential climatic changes for the region up until the 2040s.
The Influence of Pollutants on Solar Radiation
According to the study, the buildup of pollutants in the Asian Tropopause Aerosol Layer, situated at high altitude, leads to a decrease in solar radiation that reaches the Indian subcontinent. The accumulation of these aerosols triggers an abnormal cooling effect over north India and the Tibetan plateau, which in turn weakens the low-pressure system typically present in these regions.
Effects on Monsoon Circulation and Drought Severity
The weakened low-pressure system is consequential for the monsoon cycle. It results in a lessened monsoon circulation which, compounded with other climatic factors, heightens the severity of drought conditions. The observations suggest that the presence of pollutant aerosols may have been a contributing factor to a roughly 17% decrease in rainfall over central India.
Future Implications and Predictions
Given that the aerosol pollution over South Asia is predicted to persist until at least the end of the 2040s, the study anticipates more extreme El Nino events in the future. Furthermore, it predicts that future increases in industrial emissions from both east and south Asia will result in a wider and thicker layer of pollutant aerosols in the upper troposphere. This could potentially amplify the severity of drought conditions over India.
| Fact | Details |
|---|---|
| Discovery by IITM, Pune | Pollutants from South Asia amplify the effects of El Nino on monsoon, increasing drought severity in India |
| Impact on Solar Radiation | Increased pollutants reduce the amount of solar radiation, causing abnormal cooling over north India and the Tibetan plateau |
| Effect on Monsoon and Drought | Weakened monsoon circulation due to abnormal cooling leads to more severe droughts |
| Future Predictions | More extreme El Nino events and worsening droughts over India due to increases in aerosol pollution |
Conclusion From The Study
The implications of this study are far-reaching. It underscores the integral role of environmental pollutants in modifying weather patterns and exacerbating climatic events such as droughts. As aerosol pollution is set to continue for several more decades, increased industrial emissions could further contribute to creating adverse weather events. These findings underscore the urgent need to address air pollution issues to mitigate its climatic ramifications.
Last Modified: February 6, 2024