The potential impacts of climate change on hydrology were simulated with a modelling chain, whereby each climate change scenario was projected through global climate models (GCMs), regional climate models (RCMs), the DBS bias correction method, and the HYPE hydrological model1 applied on the Arctic-HYPE v2.3. A set of summary variables were derived for each sub-basin from the daily hydrological output for a historical reference period and a set of future periods. Subsequently, the relative change between the future periods and the reference period was calculated for each summary variable, climate projection, and future period.
We assess the impact of climate change on the hydro-climatic variables: long-terms means of air temperature (°C), precipitation (mm/year), river discharge (m3/s), local runoff from land (mm/year), potential evapotranspiration (mm/year), actual evapotranspiration (mm/year) and snow water equivalent (mm).
Climate change scenario2 | GCMs3 | RCM3 & domain4 | Bias correction5 | Hydrological model |
---|---|---|---|---|
RCP 8.5 | EC-Earth MPI-ESM-LR | RCA4 for MENA-CORDEX | DBS using WFDEI6 as reference | Arctic-HYPE v2.3 |
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