SASMAL S K
Articles written in Journal of Earth System Science
Volume 129 All articles Published: 15 October 2020 Article ID 0211 Research article
KRISHNAPRIYA M RABINDRA K NAYAK ALLAHUDEEN SHAIK BHUVANACHANDRA A DADHWAL V K JHA C S SHESHASAI M V R SASMAL S K PRASAD K V S R
In this study, investigation of the seasonal cycle of the tropospheric CO$_{2}$ concentration over India was carried out using the GEOS-Chem atmospheric transport model, Greenhouse gas Observation SATellite (GOSAT) retrievals, and
$\bf{Highlights}$
$\bullet$ Greenhouse gas Observation SATellite (GOSAT) L3B and L4B retrievals and
$\bullet$ The seasonal cycle over north India is composed of mixed signature of annual and semi-annual frequencies while south India experiences dominance of annual oscillation. However, the surface layer CO$_{2}$ seasonal tendency has a major negative phase during April–August and a positive phase during September–March.
$\bullet$ The net negative tendency during April–August results from the loss of CO$_{2}$ from the surface layer through horizontal advection and vertical diffusion processes that dominates the gain from vertical advection; while the net positive tendency during September–March results from the gain through vertical advection and horizontal advection and a small negative contribution from vertical diffusion.
$\bullet$ At annual scale, the surface layer over India experiences net positive gain of CO$_{2}$ concentration, which is 85% more than the net input from the surface fluxes, and is mostly contributed by large-scale transport processes.
$\bullet$ Sensitivity experiments were carried out to elucidate the semi-annual features of the seasonal cycle of CO$_{2}$ over north India in relation to the GOSAT observation. It turns out that the secondary trough during October–December on the background of net positive tendency during September–March results from the drawdown of CO$_{2}$ by the terrestrial ecosystem uptake.
Volume 129, 2020
All articles
Continuous Article Publishing mode
Click here for Editorial Note on CAP Mode
© 2021-2022 Indian Academy of Sciences, Bengaluru.