Journal of Environment and Sociobiology

Amarjeet ¹, Vineet Sharma ¹, Anil Kumar Gupta ², Arun Chakraborty ¹, Akshay Kumar Sagar ¹, Sakshi Sharma ¹

Affiliations
1 Centre for Ocean, River, Atmosphere and Land Sciences (CORAL), Indian, Institute of Technology, Kharagpur, West Bengal, India – 721302., IN
2 Department of Geology and Geophysics, Indian Institute of Technology, Kharagpur, West Bengal, India – 721302., IN

Abstract

In this study, an analysis of the relationship of 500, 700, and 850 hPa geopotential heights (GpH) with vertically integrated moisture flux divergence is examined for two selected sets of years named Dry and Wet. First, a comparison of the four different datasets, ERA-5, JRA-55, NCEP/NCAR, and MERRA-2, is done to look out for the variations and trends of geopotential SS heights from 1980-2021 and to select the best dataset for the whole analysis. Though all the datasets provide more or less the same variations and trends (except NCEP/NCAR), only ERA-5 is chosen on basis of high spatial resolution (0.25° × 0.25°) data. From the rainfall data, the dry and wet years are selected based on the Indian Meteorological Department (IMD) criteria. The variations of the standardized anomaly of different GpH are examined with the vertically integrated moisture flux divergence (VIMFD) in the selected dry and wet years. All the GpH are found to depict the condition of the less (more) trough (low-pressure area) over central India and the Bay of Bengal (BB), coinciding with the less (more) convergence of vertically integrated moisture flux (VIMF) in JJAS season of dry (wet) years.

Keywords

Geopotential Heights (GpH), Vertically Integrated Moisture Flux Divergence (VIMFD), Dry and Wet Years.

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