201. Constrained simulation of aerosol species and sources during pre-monsoon season over the Indian subcontinent
- Author
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Kravitz, Ben, Rasch, Philip, Wang, Hailong, Robock, Alan, Gabriel, Corey, Cole, Jason, Haywood, Jim, Ji, Duoying, Jones, Andy, Lenton, Andrew, Moore, John, Muri, Helene, Niemeier, Ulrike, Phipps, Steven, Schmidt, Hauke, Watanabe, Shingo, Yang, Shuting, Yoon, Jin-Ho, Bharath Kumar, D., Verma, Shubha, Boucher, Olivier, Wang, Rong, Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory (PNNL), Pacific NW Natl Lab, Richland, WA 99352 USA, Laboratory of Microbial Technology, Shandong University, Department of Environmental Sciences [New Brunswick], School of Environmental and Biological Sciences [New Brunswick], Rutgers, The State University of New Jersey [New Brunswick] (RU), Rutgers University System (Rutgers)-Rutgers University System (Rutgers)-Rutgers, The State University of New Jersey [New Brunswick] (RU), Rutgers University System (Rutgers)-Rutgers University System (Rutgers), Blackett Laboratory, Imperial College London, University of Exeter, State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Met Office Hadley Centre (MOHC), United Kingdom Met Office [Exeter], CISRO Oceans and Atmosphere [Hobart], Robarts Research Institute [Canada], University of Western Ontario (UWO), Department of Geosciences [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Max Planck Institute for Meteorology (MPI-M), Max-Planck-Gesellschaft, University of New South Wales [Sydney] (UNSW), Max-Planck-Institut für Meteorologie (MPI-M), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Danish Meteorological Institute (DMI), Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Beijing Normal University (BNU), Met Office Hadley Centre for Climate Change (MOHC), CISRO Oceans and Atmosphere, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and École normale supérieure - Paris (ENS-PSL)
- Subjects
Total organic carbon ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,010501 environmental sciences ,Spatial distribution ,Atmospheric sciences ,01 natural sciences ,Aerosol ,Indian subcontinent ,Pre monsoon ,[SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology ,[SDU]Sciences of the Universe [physics] ,13. Climate action ,[SDE]Environmental Sciences ,Environmental science ,Mass concentration (chemistry) ,Emission inventory ,Bay ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences - Abstract
This study was designed to deliver a better concurrence between model estimates and observations, of atmospheric aerosol species, and predict their spatial distribution as consistently as possible. A free running aerosol simulation ( freesimu ) in a general circulation model (GCM) was performed, and further the simulated aerosol optical depth (AOD) was constrained with the observed AOD. The present study was carried out during the pre-monsoon season and for the Tigerz experiment which was conducted at stations over the Indo-Gangetic plain (IGP) and the Himalayan foot-hills in northern India. Our formulation of the constrained aerosol simulation ( constrsimu ) was based upon an identification of the freesimu with the most consistent estimates of aerosol characteristic among the three freesimu . The three freesimu (differing in source of emissions and model horizontal resolution) were carried out with the general circulation model (GCM) of Laboratoire de Meteorologie Dynamique (LMD-ZT GCM). Black carbon (BC), organic carbon (OC), and sulfate-other water soluble (Sul-ows) estimated from constrsimu amounted to 70%–100% compared to that from freesimu being 20%–50% of their measured counterparts. Among the aerosol species, the pre-monsoon mean concentration of dust was considerably high over most part of the Indian subcontinent; the anthropogenic aerosol species were, however, specifically predominant over the IGP (mostly 8–12 μ g m −3 for Sul-ows, OC). The constrsimu estimated total submicron aerosol mass concentration revealed its alarmingly high value over the northern and north-western India (> 100 μ g m −3 and as high as 300 μ g m −3 ). While the high value of observed AOD was found being mainly due to dust (AOD due to dust greater than 0.3) over the northern–northwestern IGP, it was due to Sul-ows (AOD due to Sul-ows as high as 0.4) over the eastern IGP, eastern coastline, and the Bay of Bengal. Temporal trend of fine (FM) and coarse mode (CM) AOD from constrsimu estimates and that derived from Tigerz experiment were in phase with each other for most of the days and exhibited a strong positive correlation coefficient. Source of Tigerz aerosols was mainly due to a predominant influence of dust from Africa/west Asia followed by that from northwest India, and of anthropogenic emissions originating in the IGP. A 200% increase was inferred for potential black carbon emissions (using India emission inventory implemented in a GCM) to obtain a concurrence between observed and freesimu BC concentration.
- Published
- 2018