Abstract:
—The Indian summer monsoon rainfall (ISMR, June–
September) is an important factor in agricultural planning and the
Indian economy. The ISMR over East India (EI: ChhattisgarhBihar-Jharkhand-Odisha) is particularly significant, and it can have
an impact on the country’s average ISMR. The current study
examined projected changes in ISMR over EI with two emission
scenarios, RCP4.5 and RCP8.5, for near (2017–2040) and far-future (2041–2070) projections using a set of ten CORDEX-SA
Regional Climate Model (RCMs). To begin, the performance of
raw and bias-corrected ISMR over EI outputs from ten CORDEXSA RCMs was compared to a high-resolution (0.25 9 0.25)
gridded rainfall analysis dataset from the India Meteorological
Department (IMD) over the hindcast period (1971–2005). Following that, bias-corrected results were used to calculate ISMR
projections over EI for the near and distant futures. Most RCMs,
according to the findings, can imitate the spatial pattern of ISMR
across EI but are restricted in their ability to capture actual magnitudes. Notably, RCM prediction skill increased greatly after
employing various bias-correction approaches, the quantile mapping (QQM) bias-correction technique outperformed other current
conventional bias correction methods, and the QQM technique was
employed for ISMR future projections using RCP4.5 and RCP8.5
emission scenarios. The analysis of ISMR projections over EI
reveals that there will be more deficit rainfall years in the short
term while more excess rainfall years in the far future.
