This title appears in the Scientific Report :
2023
Groundwater in terrestrial systems modelling: a new climatology of extreme heat events in Europe
Groundwater in terrestrial systems modelling: a new climatology of extreme heat events in Europe
The representation of groundwater processes is simplified in most regional climate models (RCMs), potentially leading to biases in simulated heat waves. We introduce aunique dataset from the regional Terrestrial Systems Modeling Platform (TSMP) forced by the Max Planck Institute Earth System Model w...
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Personal Name(s): | Poshyvailo-Strube, Liubov (Corresponding author) |
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Wagner, Niklas / Görgen, Klaus / Furusho, Carina / Hartick, Carl / Kollet, Stefan | |
Contributing Institute: |
Agrosphäre; IBG-3 |
Imprint: |
2023
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Conference: | 2nd TERENO-OZCAR Conference, Bonn (Germany), 2023-09-25 - 2023-09-28 |
Document Type: |
Conference Presentation |
Research Program: |
ClimXtreme Verbundprojekt Modul C Impacts - Teilprojekt 7: IHAX - Einfluss der anthropogene Wassernutzung auf Extremereignisse in regionalen Klimasimulationen HI-CAM (CARF - CCA) Agro-biogeosystems: controls, feedbacks and impact |
Publikationsportal JuSER |
The representation of groundwater processes is simplified in most regional climate models (RCMs), potentially leading to biases in simulated heat waves. We introduce aunique dataset from the regional Terrestrial Systems Modeling Platform (TSMP) forced by the Max Planck Institute Earth System Model with Low Resolution (MPI-ESM-LR)historical boundary conditions in the context of dynamical downscaling of global climate models (GCMs) for climate change studies. TSMP explicitly represents 3Dsubsurface and groundwater hydrodynamics together with overland flow, closing the water and energy cycle from the bedrock to the top of the atmosphere. We perform ananalysis of summer heat events (i.e., a series of consecutive days with a near-surface temperature exceeding the 90th percentile) for the historical time period 1976-2005relative to the reference period 1961-1990 in a TSMP climate change scenario control run. For comparison, the analysis is repeated for an ensemble of GCM-RCMsimulations with simplified groundwater dynamics from the Coordinated Regional Climate Downscaling Experiment for European domain (EURO-CORDEX).Our results show that TSMP simulates the number of heat events consistently with the CORDEX ensemble, although there are systematic differences. Compared to theCORDEX ensemble, TSMP simulates lower mean and interannual variability in the frequency of hot days (i.e., days with a near-surface temperature exceeding the 90thpercentile) on average over Europe. The decadal change in the number of hot days is also lower in TSMP than on average in the CORDEX ensemble. TSMP systematicallysimulates fewer heat waves (i.e., heat events lasting 6 days or more) compared to the CORDEX ensemble, moreover, they are less intense. We find that Southern Europe isparticularly sensitive to groundwater coupling, while Scandinavia is the least sensitive. Therefore, an explicit representation of groundwater may be a key for bias reduction insimulated duration and intensity of heat waves, particularly in Southern Europe. The results emphasise the importance of groundwater coupling in long-term regionalclimate simulations and potential implications for climate change projections. This work is currently under review for the ESD journal. |