Supercomputing is helping researchers both to develop next-generation energy technologies and to improve current power generation methods to be safer, cleaner, and more efficient. HPC is also used to model how environmental factors will influence the future climate on a regional level, informing decision makers to support the development of new mitigation strategies.
The following is a list of recent reports submitted by users of HLRS's high-performance computing systems describing their scientific interests and research results.
Click on each title for a more detailed report. The complete reports are found on the website of the Gauss Centre for Supercomputing (GCS), the alliance of Germany's three national supercomputing centers.
21st Century Climate in Africa: Regional Climate Simulations with COSMO-CLM
The African Continent will be severely hit by climate change. A necessary building brick for counteraction are reliable projections of the African climate of our century. The CORDEX CORE initiative is designed to provide such information for the CORDEX CORE regions, among them CORDEX CORE Africa. IMK-TRO contributed to this with an ensemble of presently ten regional climate simulations performed on the Hazel Hen at HLRS Stuttgart. Results indicate dramatic changes especially in precipitation. The simulations presented here will be part of the IPCC AR6 atlas of regional climate change and the CORDEX data repository. They will be freely available for impact, adaptation and mitigation studies.
Principal Investigator: Gerd Schädler
Affiliation: Institute for Meteorology and Climate Research, Department Troposphere Research, Karlsruhe Institute of Technology
WRF Simulations to Investigate Processes Across Scales (WRFSCALE)
Numerical models are excellent tools to improve our understanding of atmospheric processes across scales since they provide a consistent 4D representation of the atmosphere. Project WRFSCALE consists of different sub-projects, applying the Weather Research and Forecasting (WRF) model at resolutions between 3 km and 100 m, performing investigations in the fields of data assimilation, bio-geoengineering and boundary layer research. By increasing the resolution to 100 m, the model starts to explicitly resolve the representation of turbulence. With such simulations and comparisons to high-resolution observations, it is the aim to better understand the turbulent boundary layer and its interaction with the underlying land surface.
Principal Investigator: Hans-Stefan Bauer
Affiliaton: Institute of Physics and Meteorology, University of Hohenheim
Terra-Neo: Towards Earth Mantle Convection Simulation with Hierarchical Hybrid Multigrid Solvers
Convection in the Earth’s mantle is the driving force behind large scale geologic activity such as plate tectonics and continental drift. As such it is related to phenomena like e.g. earthquakes, mountain building, and hot-spot volcanism. Laboratory experiments naturally fail to reproduce the pressures and temperatures in the mantle, thus simulation is a key ingredient in the research of mantle convection. However, since simulating convection in the Earth’s mantle is a very resource consuming HPC application as it requires extremely large grids and many time steps in order to allow models with realistic geological parameters, researchers turn towards GCS supercomputers to tackle this challenge.
Principal Investigator: Ulrich Rüde
Affiliaton: Lehrstuhl für Informatik 10 (Systemsimulation), Friedrich-Alexander-Universität Erlangen-Nürnberg (Germany)
Seasonal Forecasts for the Horn of Africa
Regional climate simulations at the convection-permitting scale (< 4 km) have the potential to improve seasonal forecasts, especially where complex topography hinders global models. Due to high computational costs, tests using state-of-the-art ensemble forecasts have not been performed yet. In this one-year case study, a Weather Research and Forecasting (WRF) multi-physics ensemble was used to downscale the SEAS5 ensemble forecast over the Horn of Africa. Reliability of precipitation prediction is improved, although the global model’s biases in temperature and precipitation are not reduced. Measurable added value against the global model is provided for intense precipitation statistics over the Ethiopian highlands.
Principal Investigator: Paolo Mori
Affiliation: Institute of Physics and Meteorology, University of Hohenheim
Climate Change Studies for Germany
The University of Hohenheim contributed with five regional climate simulations to the multi-model ensemble of EURO-CORDEX. The ensemble data is required to analyze the climate change signals in Europe and to provide high-resolution products for climate impact research and politics for 1971 to 2100.
Principal Investigator: Kirsten Warrach-Sagi
Affiliation: University of Hohenheim (Germany)
High-Resolution Ocean Modelling on Unstructured Meshes
Results from high-resolution simulations with the sea ice-ocean model FESOM, formulated on unstructured meshes, are presented in which ocean eddies are resolved in the North Atlantic region. By resolving ocean eddies, these features are represented by the laws of physics rather than empirical rules of thumb, as done in most existing climate simulations. A comparison with satellite data suggests that the simulated eddy fields start to become indistinguishable from observations, showing that the model passes the climatic Turing Test. It is argued that these high-resolution models have the potential to significantly increase our understanding of how the climate in general and the ocean in particular will be evolve in a warming world.
Principal Investigator: Thomas Jung
Affiliation: Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI), (Germany)