Ambient CO Levels during Winter and Summer Agricultural Burning Seasons of Northern India

Abstract

Field burning of crop residues (FBCR) has significant environmental costs in terms of concerning emissions and natural resource loss. Such burning is increasingly common in the developing world regions like India, and the ambient levels of carbon monoxide (CO), a criteria-pollutant, during such burning seasons has not been studied as yet by any research or pollution monitoring agencies in the region. In this instance, in-situ field studies were conducted in the northern Indo-Gangetic plains to study the ambient CO levels during the rice and wheat crop (the major crop residues subject to FBCR in the region) residue burning seasons. The ambient CO levels were observed to be 1.90±0.69 ppmv and 1.35±0.53 ppmv during the rice residue burning season at Pantnagar and Ludhiana respectively. During the wheat residue burning seasons, it was observed to be 0.41±0.23 ppmv at Pantnagar and 0.69±0.22 ppmv at Patiala and Ludhiana (combined). The ambient CO levels remained near the National Ambient Air Quality Standard during the study period and also crossed it several times. It was further observed that the levels were higher in case of rice residue burning season as compared to that of wheat. The long residence time of CO and the increasing FBCR practice may aggravate the problem in future.