Comparison of TRMM multi-satellite precipitation analysis (TMPA) estimation with ground-based precipitation data over Maharashtra, India

The Tropical Rainfall Measuring Mission (TRMM) is a multi-satellite precipitation product which is important for various hydro-meteorological applications. It is important to assess the correlation between precipitation records obtained by satellite and a ground observation station. The current study focuses to understand if satellite estimates can be used over ground station. The study has used bivariate correlation analysis to assess daily and 8-day composite precipitation records of TRMM satellite and Indian Meteorological Department (IMD) over Maharashtra, India, for monsoon months during 2004–2013. The Pearson’s correlation coefficient (r) varies significantly for daily and 8-day composite analysis. It was found that the 8-day composite TRMM showed strong correlation when compared to daily rainfall amounts. From the values recorded and scrutiny carried out, it was seen that the TRMM estimates were very well in synchronization with the IMD data for western region of study area. Precipitation in this region is heavily influenced by the Western Ghats which helps in exact determination of trend. Geographical influence on rainfall is a crucial thing to be addressed while conducting such studies. Research concludes that TRMM satellite estimates when considered over weekly analysis yielded better results against IMD’s rainfall making a suitable replacement for hydro-metrological studies.