Ultra high-resolution near-term hydro-meteorological projections and impact assessments over the United States and South Asia

We present near-term hydro-meteorological projections and impact assessments over the continental United States and South Asia from a hierarchical high-resolution regional modeling framework for regional climate predictions and impact assessments. Results are based on an ensemble of multi-GCM driven integrations that include two regional climate models (RegCM4 and WRF), one hydrological model (VIC) and one crop simulation model (DSSAT). All models' integrations consist of 40 years in the historic period (1966-2005) and 40 years in the near-term future period (2011-2050) under the Representative Concentration Pathway 8.5. First, we use regional climate models (RCMs) to downscale nine Global Climate Models (GFDL-ESM2M, CCSM4, NorESM1-M, MPI-ESM-MR, MIROC5, CNRM-CM5, BCC-CSM1-1, FGOALS-g2, CanESM2) in the 5th phase of Coupled Model Inter-comparison Project (CMIP5) archives to 18 km horizontal grid spacing. Further, we force the VIC-model with the bias-corrected daily fields from each of the RCM integrations at 4 km over the conterminous U.S. and at 18 km over the Upper Indus Basin in South Asia. To improve the VIC-model's skill, we calibrated the model over the conterminous U.S. at Sub-basin (HUC08) level and we extended the model to include the representation of glaciers through one-way coupling over the Upper Indus Basin. Similarly, we force the DSSAT model with bias corrected daily fields from each of the RCM integrations in the southeastern U.S. and parts of South Asia. Analyses are focused on the investigation of potential near-term hydro-meteorological change and its impact on water availability and crop production within the context of structural and parametric uncertainties in the modeling framework.