DATE2022-05-30 16:18:01
TITLEDoes increasing horizontal resolution improve the model performance in the Mediterranean? Evidence from High-Resolution Model Intercomparison Project
AUTHORSAlok Kumar Mishra (1) ,Babita Jangir (1) ,Ehud Strobach (1)
  1. 1) Volcani Institute, Agricultural Research Organization, Rishon Lezion (Israel)
ABSTRACTThe Mediterranean region is reported as one of the climate change hot-spots, posing serious threats to society, making climate scientists highly conscious of minimizing uncertainties in the present climate model simulations and improving future projections on the regional scale. Despite the efforts of the modeling community to improve the representation of the sea surface temperature (SST) over the Mediterranean Sea (MS), models still have notable bias, possibly due to insufficient resolution that limits the model capability to resolve the complex topography over the region. This study examines the reliability of CMIP6 models from the High-Resolution Model Intercomparison Project in reproducing the Mediterranean climate, focusing on the mean and extremes. Additionally, the role of the oceanic and atmospheric resolutions of the model is also investigated. All models systematically underestimated the SST at lower resolution except CMCC, which prominently overestimates over western MS and slightly underestimates over eastern MS. A finer oceanic resolution improves not only the general representation of oceanic characteristics (i.e., SST) but also atmospheric processes (wind and precipitation). These results are broadly consistent for all models; however, different models show spatially varying skills and responses of resolution for different aspects. Most models show a tendency of warming in the high-resolution simulations compared to corresponding lower-resolution simulations, leading to reduced underestimation. CMCC and MPI-ESM models show cooling with increasing oceanic resolution, resulting in a reduction of warm bias over western MS and some patches along the eastern MS coast in the CMCC and increased cold bias in MPI-ESM. Likewise, the results for enhanced atmospheric resolution have clearly beneficial impacts on certain aspects. However, an inter-model spread can be attributed to factors other than spatial resolution. Additionally, some features appear to be insensitive and do not show improvement. Keywords: Mediterranean Climate; CMIP6; HighResMIP; Added Value