Additional parameters in TRANSLATE: A standardized Climate change dataset for Ireland

The TRANSLATE project has already generated a first set of standardised climate projections, based on a selection of CMIP5 global model projections using 3 different forcing scenarios (RCP 2.6, 4.5 and 8.5).  For each scenario, a 6-member ensemble of CMIP5 simulations were dynamically downscaled to high-resolution (4 km) over Ireland using the COSMO and WRF regional models, while a larger ensemble (up to 30 members, depending on scenario) were downscaled to 12 km by the EURO-CORDEX project.  The rest of the 21^st century was divided into three 30-year periods (2021-2050, 2041-2070, and 2071-2100), and for each of these the downscaled simulations were detrended and bias-corrected (using quantile-delta mapping), and further statistically downscaled to a high-resolution observational grid. This project is now adding several more parameters like wind speed  and direction, relative humidity, and downward shortwave radiation  at the surface. The method remains much the same as used by O’Brien E and Nolan P (2023). These variables may be combined with temperature projections produced earlier to compute projections of derived indices such as evapotranspiration or renewable energy potential.

 

A high resolution (2km X 2km) reanalysis dataset is used in lieu of reference observations from 1981 to 2010. These data were generated using the WRF regional model down-scaling the ERA Interim dataset. These 30 year daily observations were used to validate the corresponding variables in regional climate models output for the same historical period (1981-2010). Ensembles of reconstructed i.e., detrended, bias-corrected, and further downscaled daily timeseries for all three parameters are now completed. Using these data, future climate change scenarios from both COSMO and Cordex ensembles are analysed relative to the historical baseline period. The most interesting selected results will be presented.

We also plan to repeat these analyses using CMIP6  based projections.