Sources and Radiative Impact of Carbonaceous Aerosols Using Four Years Ground-Based Measurements over the Central Himalayas

Abstract Climate and health in the pristine Himalayan region are largely impacted by the transport of carbonaceous aerosols from the polluted regions of Asia and Europe. Yet, there is a scarcity of source apportionment studies that can explain diurnal scale phenomena concerning various emission sour...

Full description

Saved in:
Bibliographic Details
Main Authors: Priyanka Srivastava, Manish Naja, T. R. Seshadri
Format: Article
Language:English
Published: Springer 2023-07-01
Series:Aerosol and Air Quality Research
Subjects:
Online Access:https://doi.org/10.4209/aaqr.220381
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1823862798523826176
author Priyanka Srivastava
Manish Naja
T. R. Seshadri
author_facet Priyanka Srivastava
Manish Naja
T. R. Seshadri
author_sort Priyanka Srivastava
collection DOAJ
description Abstract Climate and health in the pristine Himalayan region are largely impacted by the transport of carbonaceous aerosols from the polluted regions of Asia and Europe. Yet, there is a scarcity of source apportionment studies that can explain diurnal scale phenomena concerning various emission sources and radiative forcing. Here, we report the first simultaneous high-resolution delineation of primary organic carbon (POC) and secondary organic carbon (SOC) content and quantify the contributions of fossil fuel combustion and biomass burning over the Central Himalayas using four-year (2014–2017) online observations. Four different methods are employed to deconvolute organic carbon (OC) into POC and SOC. Unlike SOC, POC exhibits significant unimodal diurnal variations with higher values during daytime in all four methods. These methods show intra-annual variations in POC (56–80%) and SOC (20–44%) concentrations but they agree that overall POC (4.7–8 µg m−3) dominates over SOC (2.4–3.9 µg m−3). The role of crop residue burning in northern India and forest fires is shown to be dominant in spring while local heating-purpose emissions dominate in winter. Further, we show that the contribution of fossil fuel combustion (eBCff) is 3.5 times greater than that of biomass burning (eBCbb). Monthly variations in mean diurnal amplitudes of eBCff and eBCbb reveal that the differences in their amplitudes (9–32%) is smallest during April–May, depicting the relative importance of biomass emissions at the diurnal scale during spring. The estimated daily radiative forcing shows that eBCff contributes more (16.4%) atmospheric forcing than eBCbb. Atmospheric forcing from both eBCff and eBCbb are higher (19.8 and 13.0 W m−2, respectively) in the afternoon than morning. These findings underscore the need for high-resolution data when researching aerosol-radiation interaction over the Himalayan area and are vital for developing aerosol mitigation plans.
format Article
id doaj-art-3587f6da97004b638de652616a17ad32
institution Kabale University
issn 1680-8584
2071-1409
language English
publishDate 2023-07-01
publisher Springer
record_format Article
series Aerosol and Air Quality Research
spelling doaj-art-3587f6da97004b638de652616a17ad322025-02-09T12:22:54ZengSpringerAerosol and Air Quality Research1680-85842071-14092023-07-01231012010.4209/aaqr.220381Sources and Radiative Impact of Carbonaceous Aerosols Using Four Years Ground-Based Measurements over the Central HimalayasPriyanka Srivastava0Manish Naja1T. R. Seshadri2Aryabhatta Research Institute of Observational SciencesAryabhatta Research Institute of Observational SciencesDepartment of Physics and Astrophysics, University of DelhiAbstract Climate and health in the pristine Himalayan region are largely impacted by the transport of carbonaceous aerosols from the polluted regions of Asia and Europe. Yet, there is a scarcity of source apportionment studies that can explain diurnal scale phenomena concerning various emission sources and radiative forcing. Here, we report the first simultaneous high-resolution delineation of primary organic carbon (POC) and secondary organic carbon (SOC) content and quantify the contributions of fossil fuel combustion and biomass burning over the Central Himalayas using four-year (2014–2017) online observations. Four different methods are employed to deconvolute organic carbon (OC) into POC and SOC. Unlike SOC, POC exhibits significant unimodal diurnal variations with higher values during daytime in all four methods. These methods show intra-annual variations in POC (56–80%) and SOC (20–44%) concentrations but they agree that overall POC (4.7–8 µg m−3) dominates over SOC (2.4–3.9 µg m−3). The role of crop residue burning in northern India and forest fires is shown to be dominant in spring while local heating-purpose emissions dominate in winter. Further, we show that the contribution of fossil fuel combustion (eBCff) is 3.5 times greater than that of biomass burning (eBCbb). Monthly variations in mean diurnal amplitudes of eBCff and eBCbb reveal that the differences in their amplitudes (9–32%) is smallest during April–May, depicting the relative importance of biomass emissions at the diurnal scale during spring. The estimated daily radiative forcing shows that eBCff contributes more (16.4%) atmospheric forcing than eBCbb. Atmospheric forcing from both eBCff and eBCbb are higher (19.8 and 13.0 W m−2, respectively) in the afternoon than morning. These findings underscore the need for high-resolution data when researching aerosol-radiation interaction over the Himalayan area and are vital for developing aerosol mitigation plans.https://doi.org/10.4209/aaqr.220381Organic carbonBlack carbonSOCHimalayaFossil fuel and biomassRadiative forcing
spellingShingle Priyanka Srivastava
Manish Naja
T. R. Seshadri
Sources and Radiative Impact of Carbonaceous Aerosols Using Four Years Ground-Based Measurements over the Central Himalayas
Aerosol and Air Quality Research
Organic carbon
Black carbon
SOC
Himalaya
Fossil fuel and biomass
Radiative forcing
title Sources and Radiative Impact of Carbonaceous Aerosols Using Four Years Ground-Based Measurements over the Central Himalayas
title_full Sources and Radiative Impact of Carbonaceous Aerosols Using Four Years Ground-Based Measurements over the Central Himalayas
title_fullStr Sources and Radiative Impact of Carbonaceous Aerosols Using Four Years Ground-Based Measurements over the Central Himalayas
title_full_unstemmed Sources and Radiative Impact of Carbonaceous Aerosols Using Four Years Ground-Based Measurements over the Central Himalayas
title_short Sources and Radiative Impact of Carbonaceous Aerosols Using Four Years Ground-Based Measurements over the Central Himalayas
title_sort sources and radiative impact of carbonaceous aerosols using four years ground based measurements over the central himalayas
topic Organic carbon
Black carbon
SOC
Himalaya
Fossil fuel and biomass
Radiative forcing
url https://doi.org/10.4209/aaqr.220381
work_keys_str_mv AT priyankasrivastava sourcesandradiativeimpactofcarbonaceousaerosolsusingfouryearsgroundbasedmeasurementsoverthecentralhimalayas
AT manishnaja sourcesandradiativeimpactofcarbonaceousaerosolsusingfouryearsgroundbasedmeasurementsoverthecentralhimalayas
AT trseshadri sourcesandradiativeimpactofcarbonaceousaerosolsusingfouryearsgroundbasedmeasurementsoverthecentralhimalayas