Performance evaluation of chemistry transport models over India

• Published in: Atmospheric environment (1994) Vol. 71; pp. 210 - 225
• Main Authors: Moorthy, K. Krishna, Beegum, S. Naseema, Srivastava, N., Satheesh, S.K., Chin, Mian, Blond, Nadege, Babu, S. Suresh, Singh, S.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-06-2013; Elsevier
• Subjects: Aerosols; Analysis methods; Applied sciences; Atmospheric pollution; Black carbon; Chemistry transport models; Exact sciences and technology; Ocean, Atmosphere; Pollution; Sciences of the Universe; Asia; India; Aerosols; Black carbon; Chemistry transport models; Performance evaluation; Combustion residue; Carbonaceous materials; Soot; Tropical zone; Forecast model; Parameterization; Real time system; Concentration measurement; Seasonal variation; Atmospheric boundary layer; Atmospheric pollution forecasting; Air pollution; Continuous measurement; Concentration distribution
• ISSN: 1352-2310; 1873-2844
• DOI: 10.1016/j.atmosenv.2013.01.056

Using continuous and near-real time measurements of the mass concentrations of black carbon (BC) aerosols near the surface, for a period of 1 year (from January to December 2006) from a network of eight observatories spread over different environments of India, a space-time synthesis is generated. The strong seasonal variations observed, with a winter high and summer low, are attributed to the combined effects of changes in synoptic air mass types, modulated strongly by the atmospheric boundary layer dynamics. Spatial distribution shows much higher BC concentration over the Indo-Gangetic Plain (IGP) than the peninsular Indian stations. These were examined against the simulations using two chemical transport models, GOCART (Goddard Global Ozone Chemistry Aerosol Radiation and Transport) and CHIMERE for the first time over Indian region. Both the model simulations significantly deviated from the measurements at all the stations; more so during the winter and pre-monsoon seasons and over mega cities. However, the CHIMERE model simulations show better agreement compared with the measurements. Notwithstanding this, both the models captured the temporal variations; at seasonal and sub-seasonal timescales and the natural variabilities (intra-seasonal oscillations) fairly well, especially at the off-equatorial stations. It is hypothesized that an improvement in the atmospheric boundary layer (ABL) parameterization scheme for tropical environment might lead to better results with GOCART.
► A space-time synthesis of aerosol black carbon is generated over India. ► The strong seasonal variations observed, with a winter high and summer low. ► Highest BC concentration was observed over the Indo-Gangetic Plain. ► Chemistry transport model simulations deviates from the measurements. ► An improvement in the ABL parameterization scheme might improve model predictions.