Qualitative Evaluation of the High Resolution Satellite Precipitation Products with Dense Surface Rain Gauge Observations in Odisha Over a Time Period

Abstract

The study aims to the Hydro-Estimator Method (HEM) has been used as the noble approach for analysing the heavy rainfall episodes over entire Odisha using the INSAT-3D satellite- derived rainfall estimates. The findings demonstrate that, in terms of the frequency of rainfall occurrences, INSAT-3D satellite rainfall products clearly illustrated both the spatial and temporal variability in rainfall pattern of Odisha. The performance statistics with IMERG and daily merged satellite retrieved rainfall show that both the dataset corelated well with the HEM with a small deviation. For heavy rainfall events, HEM shows good skill and correlation in detecting heavy rainfall with an accuracy of 20 mm and good pattern matching with actual rainfall. Entire Odisha is considered as study area, which is located in the eastern part of India. It comprises of 30 districts and of 314 blocks spreading over an area of 155707 km2. The state has 30 districts, which are further divided into 314 revenue blocks. The rainfall data (1 year; 2016) for all the blocks of Odisha has been obtained from Special Relief Commissioner (SRC), Government of Odisha and subjected to further analysis process. The satellite derived rainfall estimates viz., HEM, were evaluated with rain  gauge based gridded data viz., IMD-GRIDDED Dataset for the year 2016 over the Odisha region at the summer monsoon period. The satellite derived rainfall estimates HE have exhibited some good results with the IMD-GRIDDED Dataset its average R2 on a daily basis for different blocks is 0.34 and on a monthly basis it is 0.44. RMSE has also been determined to different block for JJAS month. The average RMSE on daily basis is 17.7 and on monthly basis is 94.6 as shown in bias maps.