The representation of temperature over Northeast India: assessing the performance of CORDEX‑CORE model experiments

Abstract

Performance of the latest high-resolution COordinated Regional Climate Downscaling EXperiment-Coordinated Output for Regional Evaluation (CORDEX-CORE) model experiment suites for simulating temperature over Northeast India (NEI) during 1979-2005 are assessed. Three different suites of Regional Climate Models (RCMs), i.e., COSMO, RegCM4.7 and REMO suites dynamically downscaled from three different Global Circulation Models (GCMs) available over the CORDEX South Asia domain are considered. The three RCMs are evaluated to assess the performance in simulating the spatial pattern of temperature over the study area. The model experiments could simulate pre- and post-monsoon temperatures fairly well as compared to monsoon and winter seasons. The RCMs show a higher positive correlation coefficient (CC) of 0.9 – 0.98. Over the majority of NEI, the added value (AV) and Brier skill score (BSS) exhibit positive values of 0.4-0.8 and 0.2-0.8 respectively, indicating additional information and/or improvement after downscaling. The inter-comparisons show that the present-day temperature over the study region is better captured in the ensemble than in the individual model. Individually, the MPI_LR_COSMO model better simulates the spatial pattern of temperature with a higher spatial correlation of ~ 0.956 than the other RCMs. The temperature extremes are also well represented spatially by the model. Overall, the COSMO model experiment suites were identified to be the best with the corresponding observation across the year over NEI.