Publications

Bran, SH; Jose, S; Srivastava, R (2018). Investigation of optical and radiative properties of aerosols during an intense dust storm: A regional climate modeling approach. JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS, 168, 21-31.

Abstract
The dynamical and optical properties of aerosols during an intense dust storm event over the Arabian Sea have been studied using Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) and space borne instruments such as MODIS, MISR, CALIPSO and CERES during the period 17 to 24 March, 2012. The model captures the spatio-temporal and vertical variations of meteorological and optical parameters, however an overestimation in simulated aerosol optical parameters are observed when compared to satellite retrievals. The correlation coefficients (R) between simulated and observed AOD from MODIS and MISR are found to be 0.54 and 0.32 respectively. Model simulated AOD on dusty days (20 and 21 March 2012) increased by 2-3 times compared to non-dusty days (17 and 24 March 2012) and the single scattering albedo (SSA) and the asymmetry parameter increased from 0.96 to 0.99 and from 0.56 to 0.66, respectively. The R between simulated shortwave (SW) radiation at top of the atmosphere (TOA) and TOA SW radiation obtained from CERES is found to be 0.43, however the model simulated SW radiation at the TOA showed an underestimation with respect to CERES. The shortwave aerosol radiative forcing (SWARF) during the event over surface and TOA are similar to-19.3 and similar to-14.2 Wm(-2) respectively, which is about 2-5 times higher when compared to the respective forcing values during non-dust days. Estimated net radiative forcing was in the range of -13 to -21 Wm(-2) at TOA and -12 to -20 Wm(-2) at the surface. The heating rate during event days within the lower atmosphere near 850 hPa is found to 0.32 - 0.4 K day(-1) and 0.18 - 0.22 K day(-1) on dusty and non-dusty days, respectively. Results of this study may be useful for a better modeling of atmospheric aerosols and its optical and radiative properties over oceanic region.

DOI:
10.1016/j.jastp.2018.01.003

ISSN:
1364-6826