Contrasting features of winter-time PM pollution and PM-toxicity based on oxidative potential: A long-term (2016-2023) study over Kolkata megacity at eastern Indo-Gangetic Plain.

The present study is an attempt to understand the level of PM pollution and its toxicity based on the oxidative potential (OP) during the winter-time pollution period over Kolkata, a megacity at the eastern most parts of Indo-Gangetic Plain (IGP) during the period of 2016-2023. We have assessed the effectiveness of the Government of India's national mission, the National Clean Air Program (NCAP) in PM reduction over this city, and the study revealed that the mission has been efficacious in lessening the PM load by 28 % from pre-NCAP (2016-2019) to post-NCAP (2021-2023) periods. Several policy interventions reduced the contributions from various anthropogenic sources; however, biomass/solid waste burning remained a major concern with no significant reduction.

Identification of sources of coarse mode aerosol particles (PM) using ATR-FTIR and SEM-EDX spectroscopy over the Himalayan Region of India.

This study attempts to examine the morphological, elemental and physical characteristics of PM over the Indian Himalayan Region (IHR) using FTIR and scanning electron microscopy-energy dispersive X-ray (SEM-EDX) analysis. The study aimed at source identification of PM by exploring the inorganic ions, organic functional groups, morphology and elemental characteristics. The pollution load of PM was estimated as 63 ± 22 μg m; 53 ± 16 μg m; 67 ± 26 μg m and 55 ± 11 μg m over Mohal-Kullu, Almora, Nainital and Darjeeling, respectively.

Acidity and oxidative potential of atmospheric aerosols over a remote mangrove ecosystem during the advection of anthropogenic plumes.

To investigate the acidity and the water-soluble oxidative potential of PM, during the continental biomass-burning plume transport, a three-year (2018-2020) winter-time campaign was conducted over a pristine island (21.35°N, 88.32°E) of Sundarban mangrove ecosystem situated at the shore of Bay of Bengal.

A district-level emission inventory of anthropogenic PM from the primary sources over the Indian Indo Gangetic Plain: Identification of the emission hotspots.

A district-wise emission inventory was made for the states and union territories (UTs) of the Indian Indo-Gangetic Plain for the base year of 2018 to estimate the emissions of PM from various sectors. In addition to conventional sectors, emissions from road dust, fossil-fuelled irrigation pumps, and construction dust were also taken into account. Total primary anthropogenic PM emission was estimated to be 3157.

PM pollution exceeding Indian standard over a semi-urban region at eastern IGP: Chemistry, meteorological impact, and long-range transport.

A year-long study (January-December 2019) on the chemical characterization and meteorological impact on PM was conducted over a semi-urban station, Shyamnagar, in the easternmost part of the Indo-Gangetic Plains (IGP). PM concentrations (Mean = 81.69 ± 66.

A year-long study on PM and its carbonaceous components over eastern Himalaya in India: Contributions of local and transported fossil fuel and biomass burning during premonsoon.

A year-long (March 2019-February 2020) study on the characterization of fine mode carbonaceous aerosols has been conducted over a high altitude urban atmosphere, Darjeeling (27.01°N, 88.15°E, 2200 m asl) in eastern Himalaya.

High rise in carbonaceous aerosols under very low anthropogenic emissions over eastern Himalaya, India: Impact of lockdown for COVID-19 outbreak.

The present study has been conducted to investigate the relative changes of carbonaceous aerosols (CA) over a high altitude Himalayan atmosphere with and without (very low) anthropogenic emissions. Measurements of atmospheric organic (OC) and elemental carbon (EC) were conducted during the lockdown period (April 2020) due to global COVID 19 outbreak and compared with the normal period (April 2019). The interesting, unexpected and surprising observation is that OC, EC and the total CA (TCA) during the lockdown (OC: 12.

Relative role of black carbon and sea-salt aerosols as cloud condensation nuclei over a high altitude urban atmosphere in eastern Himalaya.

The present study is an attempt to investigate the relative role of black carbon (BC) and sea-salt aerosols on the CCN activation over a high altitude station, Darjeeling (27.1° N and 88.15° E, 2200 m asl) at eastern Himalaya.