RESEARCH AREAS
1) AEROSOL CLIMATE FORCING AGENTS
We study aerosol black and brown carbon (BC and BrC) and humic-like substances (HULIS) using coupled chemical-optical approaches to understand their sources, atmospheric processing and effects on regional climate.
Currently, we are looking into aerosol climate forcing in the Norwegian Arctic as part of the Indian Arctic Expedition, and also in the eastern Indo-Gangetic Plain.
We are initiating investigations into BC, BrC and HULIS characteristics in the northwestern Himalayas to better understand the role of aerosols in driving climate change in this vulnerable region.
Related papers: Rawat et al., (2022, Env. Sci. Pollut. Res); Rana et al., (2019; Atmos. Res); Rana et al., (2020; Sci. Total. Environ.); Rana et al., (2023, Atmos. Environ.); Mukherjee et al., (2020, Environ. Pollut.); Dey et al., (2021, Environ. Sci. Process. Impacts); Dey et al., (2023, STOTEN), etc.
2) SOURCE APPORTIONMENT OF FINE MODE AEROSOL
We chemically speciate fine mode aerosol and employ receptor models for quantitative source apportionment, especially for biomass burning and industrial emissions.
Our major focus so far has been on the eastern IGP and SE Asia. Currently, we are planning to characterize biomass burning and biogenic emissions in the Himalayan context.
Related papers: Lan et al., (2021, Environ. Pollut.); Tham et al., (2019, Environ. Pollut.); Mao et al., (2021, Elemen. Sci. Anthrop.), etc.
3) POPULATION EXPOSURE TO AEROSOLS
We characterize human exposure to size-segregated aerosols in outdoor and indoor settings, and employ particle deposition models to estimate respiratory tract deposition.
We are actively involved in studying exposure from residential fuel use in NE India (Assam, Meghalaya, Arunachal Pradesh) and the northwestern Himalayas (Himachal Pradesh, Uttarakhand).
Related papers: Jia et al., (2020; Sci. Total Environ., 2021; Environ. Pollut.); Sharma et al., (2023; Sci. Total Environ.)
4) RECONSTRUCTING HISTORICAL POLLUTANT DEPOSITION
We use remote lake sediments as archives to reconstruct historical pollutant deposition profiles on regional scales. We then compare pollutant deposition fluxes with chemical transport model outputs.
We have previously worked on BC and trace metal deposition profiles in the NE USA and the Finnish Arctic, and are currently working on Himalayan lakes.
Related papers: Jyethi et al., (In preparation; Atmos. Environ.); Sarkar et al., (2015; J. Geophys. Res. Atmos.)
5) OTHER RESEARCH DIRECTIONS
Aerosol acidity and its neutralization, and secondary organic carbon
-
Sharma et al., (2022; Chemosphere); Zhang et al., (2019; Sci. Total Environ.); Jia et al., (2018; Atmos. Chem. Phys.); Jia et al., (2018; Chemosphere), etc.
Factors affecting long-term tropospheric ozone profiles
-
Chen et al., (2020; Atmos. Environ.)
Satellite- and model-based evaluation of long-term aerosol profiles
-
Zhang et al., (2022; Atmos Chem & Phys Disc. ); Rawat et al., (2019; Atmos. Environ.)
Source apportionment of road dust-associated trace metals
-
Kolakkandi et al., (2020; Sci. Total. Environ.)
Sources and atmospheric processing of tropospheric halocarbons
-
Sarkar et al., (2018; Sci. Total Environ.)