Simulation of trace gases and aerosols over the Indian domain: evaluation of the WRF-Chem model
M. Michael1, A. Yadav1, S. N. Tripathi1,2, V. P. Kanawade1, A. Gaur1, P. Sadavarte3, and C. Venkataraman31Department of Civil Engineering, Indian Institute of Technology, Kanpur, India 2Centre for Environmental Science and Engineering, Indian Institute of Technology, Kanpur, India 3Department of Chemical Engineering, Indian Institute of Technology, Mumbai, India
Received: 17 Dec 2013 – Accepted for review: 20 Dec 2013 – Discussion started: 16 Jan 2014
Abstract. The "online" meteorological and chemical transport Weather Research and Forecasting/Chemistry (WRF-Chem) model has been implemented over the Indian subcontinent for three consecutive summers in 2008, 2009 and 2010 to study the aerosol properties over the domain. The model simulated the meteorological parameters, trace gases and particulate matter. Predicted mixing ratios of trace gases (Ozone, carbon monoxide and sulfur dioxide) are compared with ground based observations over Kanpur. Simulated aerosol optical depth are compared with those observed at nine Aerosol Robotic Network stations (AERONET). The simulations show that the aerosol optical depth of the less polluted regions is better simulated compared to that of the locations where the aerosol loading is very high. The vertical profiles of extinction coefficient observed at the Kanpur Micropulse Lidar Network (MPLNET) station is underpredicted by the model by 10 to 50% for altitudes greater than 1.5 km and qualitatively simulate the elevated layers of aerosols. The simulated mass concentration of black carbon shows a correlation coefficient of 0.4 with observations. Vertical profiles of black carbon at various locations have also been compared with observations from an aircraft campaign held during pre-monsoon period of 2008 and 2009. This study shows that WRF-Chem model captures many important features of the observed atmospheric composition during the pre-monsoon season in India.
Michael, M., Yadav, A., Tripathi, S. N., Kanawade, V. P., Gaur, A., Sadavarte, P., and Venkataraman, C.: Simulation of trace gases and aerosols over the Indian domain: evaluation of the WRF-Chem model, Geosci. Model Dev. Discuss., 7, 431-482, doi:10.5194/gmdd-7-431-2014, 2014.