Connecting Crop Productivity, Residue Fires, and Air Quality over Northern India

Abstract:

The agriculturally fertile region of northwestern India is known as the “breadbasket” of the country, producing two-thirds of food grains, with wheat and rice as the principal crops grown under the crop rotation system. Agricultural data from India indicates a 25% increase in the post-monsoon rice crop production in Punjab during 2002-2016. NASA’s A-train satellite sensors detect a consistent increase in the vegetation index (net 17%) and post-harvest agricultural fire activity (net ~60%), leading to nearly 60% increase in aerosol loading over the populous Indo-Gangetic Plain (IGP) in northern India. The ground-level particulate matter (PM2.5) downwind over New Delhi shows a concurrent uptrend of net 60%. The effectiveness of a robust satellite-based relationship between vegetation index-a proxy for crop amounts, and post-harvest fires-a precursor of extreme air pollution events, has been further demonstrated in predicting the seasonal agricultural burning. Such predictions can serve as a guideline for planning and preparedness related to air quality events. Furthermore, the relationship between NDVI and fire activities would play an important role in tracking and evaluating the efforts towards reducing the burning activities. Rising levels of rice crop fires and deteriorating air quality over IGP is a serious health concern demanding urgent remediation policies, such as an efficient crop residue management system, towards eliminating open field burning, thereby mitigating episodic hazardous air quality over northern India. A similar analysis of the wheat burning season is underway and will likely be presented in this talk. Additionally, an attempt will be made to analyze this year’s crop burning season with an emphasis on how COVID-19 led lockdown and reduced economic activities have impacted (or not) agricultural practices over the region.