Very high particulate pollution over northwest India captured by a high-density in situ sensor network

Abstract

Exposure to particulate matter less than 2.5 µm in diameter (PM2.5) is a cause of concern in cities and major emission regions of northern India. An intensive field campaign involving the states of Punjab, Haryana and Delhi national capital region (NCR) was conducted in 2022 using 29 Compact and Useful PM2.5 Instrument with Gas sensors (CUPI-Gs). Continuous observations show that the PM2.5 in the region increased gradually from < 60 µg m−3 in 6–10 October to up to 500 µg m−3 on 5–9 November, which subsequently decreased to about 100 µg m−3 in 20–30 November. Two distinct plumes of PM2.5 over 500 µg m−3 are tracked from crop residue burning in Punjab to Delhi NCR on 2–3 November and 10–11 November with delays of 1 and 3 days, respectively. Experimental campaign demonstrates the advantages of source region observations to link agricultural waste burning and air pollution at local to regional scales.

Quantifying the dominant sources influencing the 2016 particulate matter pollution episode over northern India

“…1) which limits assessment of the model's performance in simulating the variability in surface pollution over the region with greatest fire activities. It is, therefore, crucial to monitor air quality in the biomass-burning source regions of NW India, in addition to in the major cities, as was also emphasised by Singh et al 62…”

Air pollution from biomass burning in India

“…The Aakash Project, 'An Interdisciplinary Study towards Clean Air, Public Health and Sustainable Agriculture: The Case of CRB in North India' was launched by the Research Institute of Humanity and Nature (RIHN), Kyoto, Japan in 2020. The intensive measurement campaign performed under the Aakash project from late September to mid November, 2022 confirmed CRB as the major cause of increased PM 2.5 load in rural, semi-rural and urban areas of the Northwestern (NW) IGP (Singh et al 2023). The 2009 groundwater preservation act has led to a shift in cropping patterns, which has further aggravated the CRB, leading to severe air pollution episodes over the years due to overlapping of CRB episodes and firecracker emissions during November (Kant et al 2022).…”

“…Airshed-based management calls for integrated air quality management strategies across city/state borders to find solutions to the problem of air pollution (Guttikunda et al 2023). The severe haze episodes of Delhi are a good example of regional cross-border transport of pollutants in IGP (Singh et al 2023). The long-range transport of CRB emissions from NW India is noticed even in the eastern Himalayas (Mukherjee et al 2022a).…”

“…nasa.gov/) with a VIIRS sensor aboard showed 21 509 and 7006 fires in Punjab and Haryana, respectively. Under the Aakash project, a comprehensive campaign was led by RIHN along with various institutions in IGP in September-November 2022 (Singh et al 2023). To capture the influence of CRB emissions, a dense network of 32 compact and useful PM 2.5 instruments with gas sensors and 7 P-sensors was deployed in Punjab, Haryana, Delhi NCR and western Uttar Pradesh.…”

“…Air pollution due to ABB is a cause for concern in India (Singh et al 2023). Prevalent types of ABB that are active throughout the year in India include wood burning for cooking and heating purposes and open waste burning, while CRB is episodic in nature, causing severe haze episodes (Sawlani et al 2019).…”