ENVIRONMENT AND ENERGY

The Earth is a dynamic system, various physical processes lead to deformations of the Earths surface or mass transport in its interior. Quantifying the changes with the help of measurements is a key task of geodesy, for instance to make signals attributed to climate change visible. For this, reference systems and reference surfaces are required. E.g. sea level rise refers to the so called Mean Sea Surface (MSS), or the geoid as an equipotential surface is required to show mass transport. The reference surfaces can be determined from hundreds of million measurements collected by satellites. Due to the characteristics of the collected data and the complexity of the surfaces, high performance computing is required for the numerical analysis

In July 2021, a devastating flood hit Central and Western Europe, causing severe damage, especially in the Ahr region in Germany. Researchers at the University of Bonn investigated the role of soil moisture in intensifying this extreme event. Using the JUWELS supercomputer at Forschungszentrum Jülich, they simulated varying soil moisture conditions to assess its impact on precipitation. The findings suggest that land surfaces contributed significantly to the heavy rainfall, with potential for even more precipitation under wetter soil moisture conditions. These insights can help to improve understanding of land-atmosphere interactions and disentangle drivers of extreme events.

Irradiation modeling is a crucial aspect of integrated photovoltaic (PV) system yield prediction and optimizations of the design and dimensions of PV systems. Shading models typically rely on high-resolution topography data that includes buildings and vegetation. However, the cost and limited availability of such data pose significant challenges. In this project, we took an innovative approach by considering an alternative source of topography data: maps. Specifically, we focused on the OpenStreetMap (OSM) due to its open-data availability. While maps cannot be directly used for irradiance modeling, we explored novel approaches to overcome this challenge.

The regular ups and downs of tides are phenomena obvious to any observer of the sea. Less known is that ocean tides also undergo small changes over time, for reasons that are not yet fully understood. In this project, large simulations with a global three-dimensional ocean model were performed to understand the extent to which ocean warming and the resultant increase in the vertical density structure have contributed to changes in the largest tidal wave, M2, from 1993 to 2020. Evidence was found that upper ocean warming is the leading cause for present weakening of the size of M2 across entire ocean basins. In turn, more tidal energy is currently being transferred from M2 to three-dimensional waves in the ocean’s interior.

Geothermal energy is vital for renewable power and heating. To improve project safety and efficiency, scientists employ various methods to understand subsurface processes. Monitoring earthquakes is key and reveals how the subsurface reacts to different factors. However, interpreting seismic recordings is challenging due to complex interactions and background noise. Underground processes are complicated by fluids and fault systems. Our project uses computer simulations to analyze seismic waves, enhancing our ability to pinpoint small earthquakes accurately. This helps understanding seismic triggers and reducing hazards. Additionally, we utilize recorded background noise to directly investigate subsurface structures, maximizing data insights.

More food for a growing human demand needs more water to produce it. Nevertheless, global water resources are limited. Without appropriate action towards a most efficient and most sustainable water use, the world will run into a severe water crisis.

In the BMBF research project ViWA we show how High Performance Computing using SuperMUC-NG can open new ways to create the necessary knowledge for action towards more efficient and sustainable water use in agriculture. Complex global crop growth simulations based on climate and environmental data show how water could globally be saved through better farm management. Comparing simulations with actual global crop growth observations using Sentinel-2 satellites create a global monitoring system,…

Due to a warming atmosphere and ocean, accelerated melting of the Greenland ice sheet and glaciers contribute increasingly to global sea level rise. We investigate this effect by reproducing observed sea level, temperature and salinity of the northern North Atlantic Ocean in a numerical ocean model. We compared different model simulations to situ observations and satellites data. Adding realistic Greenland melting results in a better model agreement with data, especially in Baffin Bay. Our study suggests that further work should focus on improving model resolution souch that small-scale processes can be well represented.

A team of researchers led by Prof. Xiaoxiang Zhu at the Technical University of Munich are using high-performance computing resources at the Leibniz Supercomputing Centre to create the first-ever 3D/4D dataset on urban morphology of settlements, joining traditional remote sensing data with social media content.

Clouds and precipitation are the major source of uncertainty in numerical predictions of weather and climate. A common analysis of polarimetric radar observations and synthetic radar data from numerical simulations provides new methods to evaluate models. Using the Terrestrial Systems Modeling Platform, researchers conducted ensemble simulations for multiple summertime storms over north-western Germany. The simulated cloud processes were compared in the radar space using a forward operator with the measurements from X-band polarimetric radars. In addition, sensitivity studies were conducted using different background aerosol states and land cover types in the model to better understand land-aerosol-cloud-precipitation interactions.

Geological processes are generally quite complex and occur under a wide range of thermodynamic conditions. The structure and the properties of crystalline and non-crystalline phases in the Earth’s interior are often not accessible directly and must be investigated by experiments and by numerical simulations. In this project, we use predictive molecular simulation approaches to establish relations between structural properties of relevant phases, in particular oxide and silicate glasses and melts and aqueous fluids, at high temperatures and high pressures and their respective thermodynamic and physical properties.

In the framework of the ASCETE (Advanced Simulation of Coupled Earthquake and Tsunami Events) project, the computational seismology group of LMU Munich and the high performance computing group of TUM jointly used the SuperMUC HPC infrastructures for running large-scale modeling of earthquake rupture dynamics and tsunami propagation and inundation, to gain insight into earthquake physics and to better understand the fundamental conditions of tsunami generation. The project merges a variety of methods and topics, of which we highlight selected results and impacts in the following sections.

The ExaHyPE SuperMUC-NG project accompanied the corresponding Horizon 2020 project to develop the ExaHyPE engine, a software package to solve hyperbolic systems of partial differential equations (PDEs) using high-order discontinuous Galerkin (DG) discretisation on tree-structured adaptive Cartesian meshes. Hyperbolic conservation laws model a wide range of phenomena and processes in science and engineering – together with a suite of example models, an international multi-institutional research team developed two large demonstrator applications that tackle grand challenge scenarios from earthquake simulation and from relativistic astrophysics.

A multi-institutional team of researchers is developing a data assimilation framework for coupled atmosphere-land-surface-groundwater models. These coupled models, which potentially allow a more accurate description of the coupled terrestrial water and energy fluxes, in particular fluxes across compartments, are affected by large uncertainties related to uncertain input parameters, initial conditions and boundary conditions. Data assimilation can alleviate these limitations and this project is focused in particular on the value of coupled data assimilation which means that observations in one compartment (e.g., subsurface) are used to update states, and possibly also parameters, in another compartment (e.g., land surface).

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.

To avoid dangerous climate change, we have to reduce the emission of greenhouse gases radically. This requires – among other measures – an increase of renewable sources of energy like solar and wind. In 2019, already a quarter of Germanys electricity demand has been met by wind power. In order to increase this share, one has to develop sites in hilly terrain. High resolution models are required to assess the suitability of candidate sites with respect to turbulence intensity, power production and variability. This project supports the development of the test-site WINSENT, which is located on the Swabian Alp near Stuttgart.

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.

In nuclear fusion experiments, researchers routinely heat hot gases up to temperatures of 100 million degrees in order to create the conditions needed for energy-producing fusion reactions. Turbulence is one of the main obstacles on the way to sustaining these conditions reliably. A particular challenge is found in the plasma edge, where turbulence is suppressed by a self-organized transport barrier. Researchers from the Max-Planck Institute for Plasma Physics have made important progress to understanding the turbulence in this region, leveraging resources provided by the Gauss Centre for Supercomputing.

Rotating convection is ubiquitous in geophysical systems. In generates the Earth magnetic field, stirs the deep atmospheres of giant planets and possibly also drives their strong surface winds. A thorough understanding of these objects requires comprehensive insight into the physics of turbulent convective flows that are strongly constrained by Coriolis forces. Numerical simulations reveal the full three-dimensional structure of the flow, and can be used to guide theoretical modeling.

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.

A new avenue towards the study of the Planetary Boundary Layer (PBL), namely direct numerical simulation, is pursued in this project. The geophysical problem—characterized by enormous number of degrees of freedom—is condensed to its fluid mechanical core and solved explicitly which does not require assumptions or closures for the turbulent exchange of heat pollutants, heat and momentum: It rather represents the whole cascade of turbulent motion in a miniature problem. For the first time, this allows to quantify and understand surface fluxes without utilization of simplifying assumptions and theories such as Monin—Obukhov Similarity Theory.

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.

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.

Hydrometeorological extremes, such as droughts and floods are one of the grand challenges of our future and pose great interest and concern for water management and public safety. Hence, the ClimEx project disaggregates the response of the climate system into changing anthropogenic forcing and natural variability by analyzing a novel large-ensemble of climate simulations, operated using High-Performance Computing. The comprehensive new dataset (CRCM5-LE) generated 50 transient independent and evenly likely realizations of the past and the future climate (1950-2099) over two large domains (Europe, Eastern North America) in high spatial (12km) and temporal (1h-1d) resolution. The resulting 7500 model years allow for a thorough analysis of…

Using the Model for Prediction Across Scales (MPAS), four years of climate simulations at convection-permitting resolutions where carried out using a variable 30-3km resolution mesh, transitioning the so-called gray zone of convection around 5-10km. The comprehensive data set generated following the protocol of the CORDEX Flagship Pilot Study (FPS) on convection-permitting climate simulations will allow the CORDEX-FPS community to study the added value of global, variable-resolution simulations down to convective scales over traditional approaches employing regional climate models and/or coarse horizontal resolutions.

Without its magnetic field, life on Earth’s surface is impossible, since the magnetic field screens us from deadly solar radiation. In order to gain a better understanding of the generation of Earth’s magnetic field and heat flow in the Earth--which is crucial for understanding Earth's history--scientists have performed large scale simulations of crystalline and liquid iron alloys at conditions of Earth’s core, up to 6000K and over 300 million atmospheres of pressure, and have computed the electrical and thermal conductivity. The computationally very intensive first-principles molecular dynamics simulations for fluids required more than 60 million core hours of computing time on SuperMUC.

Much of what one refers to as geological activity of the Earth arises from convective processes within the Earth’s mantle that transport heat from the deep interior of our planet to the surface. One of the major challenges in the geosciences is to constrain the distribution and magnitude of the resulting vast forces that drive plate tectonics. Mantle flow also provides boundary conditions - thermal and mechanical - to other key elements of the Earth system (e.g., geodesy, geodynamo/geomagnetism). This makes fluid dynamic studies of the mantle essential to our understanding of how the entire planet works. In a long-term effort, scientists at the Ludwig-Maximilians-Universität München strive for improved computational models of the Earth's…

Data Assimilation is an integral tool to enable precise forecasts and becomes increasingly important to derive the values of uncertain parameters due to lack of observations. Numerical models of Earth system compartments are coupled in order to simulate physically consistent water and energy fluxes in the subsurface-landsurface-atmosphere system. Such model systems become increasingly important to analyze and understand the complex processes at boundaries of terrestrial compartments and interdependencies of states across these boundaries. As such, data assimilation for these coupled systems needs to be developed.

The planetary boundary layer (PBL) is the lower layer of the troposphere, the layer that directly feels surface effects on time scales smaller than a day. Planetary boundary layers are important in climatology—modulating the fluxes between atmosphere, land and ocean—, and in meteorology—influencing weather conditions—, but key properties remain poorly understood, largely because the PBL is turbulent, and understanding and characterizing the multi-scale nature of turbulence remains challenging. High-performance computing and direct numerical simulations are decisively contributing to advance our understanding of PBL properties.

Modelling of the regional present day as well as future climate is of great interest both scientifically as well as for applications. The “Regional Climate and Water Cycle Group” at KIT Karlsruhe uses the COSMO-CLM regional climate model for detailed climate simulations in various parts of the world. Many of these quite expensive and storage intensive runs are performed on Hazel Hen at HLRS. After giving a motivation for high resolution climate modelling, the scientists briefly describe some technical aspects like nesting and ensemble building and then go to a short presentation of some results concerning the future climate in Baden-Württemberg.

Understanding the physics of earthquake rupture occurring on multiple scales and at depths that cannot be probed directly is a ‘Grand Challenge’ of Earth sciences. Geophysicists at the Ludwig-Maximilians-Universität use the in-house-developed SeisSol earthquake simulation software to improve fundamental comprehension of earthquake dynamics by numerical simulation of complicated wave and rupture phenomena.

Static 3-D city models are well established for many applications such as architecture, urban planning, navigation, tourism, and disaster management. However, they do not represent the dynamic behavior of the buildings and other infrastructure (e.g. dams, bridges, railway lines). Such temporal change, i.e. 4-D, information is demanded in various aspect of urban administration, especially for the long-term monitoring of building deformation. Very high resolution spaceborne Synthetic Aperture Radar (SAR) Earth observation satellites, like the German TerraSAR-X and TanDEM-X provide for the first time the possibility to derive both shape and deformation parameters of urban infrastructure on a continuous basis.

Gas exchange across water surfaces receives increasing attention because of its importance to the global greenhouse budget. At present, most models used to estimate the gas flux only consider wind-shear. To improve the accuracy of the predictions a detailed study of buoyancy-driven gas transfer, which is a major contributor at low to moderate wind-speed, is necessary.  The main challenge lies in resolving the extremely thin gas concentration boundary layer. To address this, direct numerical simulations (DNS) of gas transfer induced by surface-cooling were performed on SuperMUC using a numerical scheme that is capable of resolving the thin diffusive layers on a relatively coarse mesh while avoiding spurious oscillations of the scalar…

The SMOC (SubMesoscale Ocean Modelling for Climate) project aimed to shed light on the role of submesoscale turbulent processes in the overall functioning of the ocean. Leveraging HPC power, the researchers in particular tried to get answers to: A) how deep do submesoscale fronts penetrate and can they be a significant source of dissipation for the ocean circulation away from the surface?, and B) to which extent do submesoscale fronts participate in the transfer into the deep ocean of the near-inertial energy injected by the wind at the ocean surface?

Turbulence-chemistry interaction in well characterized partially premixed and premixed laboratory-scale experiments has been investigated numerically by two different methods (M1 & M2) based on the large eddy simulation (LES) technique. It could be shown that the developed transported filtered density function method (M1) is capable of reproducing the turbulence chemistry interaction in the investigated opposed jet flame configurations. The flame resolved simulations (M2) revealed the importance of flame wrinkling and scalar geometry for flame propagation and allowed for further development of sub-filter models for future LES.

Using high resolution direct numerical simulations of a flow seeded with particles around a sphere, an international research team aimed at studying the hydrodynamic problem of collisions among particles in the potentially turbulent wake of a sphere. HPC system JUQUEEN of JSC served as computing platform for this challenging simulation project.

Two-phase flows with water droplets greatly affect the thermal-hydraulic behaviour in the containment of a Pressurized Water Reactor (PWR). In order to predict the local thermal-hydraulic behaviour in a real containment in the case of a severe accident, scientists of the University of Stuttgart generated a three-dimensional geometry of a model containment based on a German PWR. 

The dynamic behavior of the atmosphere is driven by processes on a wide range of spatial and temporal scales. In a project run by scientists of the Heidelberg University, those parts of model systems which describe the fluid dynamics and the temperature evolution were investigated. The models are formulated in terms of the velocity, temperature, pressure, and density. The researchers employ a hierarchy of different physical models with an increasing degree of complexity. The task of predicting the evolution of tropical cyclones is a typical challenging example.

In order to develop economic, efficient, and reliable wind turbines, the knowledge of the mechanisms that evoke transient aerodynamic loads effecting blades, tower, and the nacelle is essential. Using high performance computing technologies, researchers of the University of Stuttgart used high-fidelity Computational Fluid Dynamics (CFD) methods to accurately predict these unsteady loads. Particular interest was paid on the interaction of wind turbine and atmospheric boundary layer.

Exploiting the computing power and memory capacities of HPC system SuperMUC, scientists of the Technische Universität München aimed at providing a global high resolution gravity field model with hitherto unprecedented accuracy and resolution. The model can be now be used by the scientific community as a surface reference for climate studies and it serves e.g. as main input for geophysical analyses and for the determination of the ocean circulation patterns.

Scientists of the RWTH Aachen University have carried out a peta-scale direct numerical simulation (DNS) of a temporally evolving lean premixed methane/air jet flame. The DNS is intented to closely mimic gas turbine combustion and can be regarded as an idealized representation of a premixed flame element inside a jet burner. To realize high resolution of flame and turbulence and to obtain converged statistics, the simulation domain was discretized with almost three billion grid points which together with the chemistry model resulted in nearly 100 billion degrees of freedom.

Predicting weather and climate and its impacts on the environment, including hazards such as floods, droughts and landslides, continues to be one of the main challenges of the 21st century – in particular for the European region as it is exposed to intense Atlantic synoptic perturbations. Scientists performed for the first time long climate simulations over the European domain at a very fine cloud-permitting resolution of about 4 km with explicitly resolved convection and a sharp representation of orography, thanks to the possibility of running very computationally and data storage demanding simulations on SuperMUC.

Scientists of the University of Duisburg-Essen pushed further the state of the art by simulating large-scale coal and biomass flames in furnaces that have been studied in detail experimentally – the Instituto Superior Técnico and the Brigham Young University furnace. Within this project, the largest large eddy simulation (LES) of coal combustion ever to be computed provided high-resolution scalar profiles within the furnace, which allowed investigating the conditions that coal particles are subjected to in these applications and to compute particle combustion histories. LES is able to provide insights to the phenomena occurring in this type of application that are currently not available through experimental means.

Leveraging the high-performance computing capabilities of the HLRS supercomputing infrastructure, scientists of the Theoretical Materials Physics Group of the Paderborn University managed to trace interface defects in amorphous/crystalline silicon heterojunction solar cells. Visualizing the processes with atomic resolution they were able to characterize the processes that compromise the solar cells' efficiency. The findings will help to optimize the solar cells further and to decrease production costs.

Thanks to the availability of HLRS’s petascale HPC system Hornet, researchers of the Institute of Physics and Meteorology of the University of Hohenheim were able to run a highly complex climate simulation for a time period long enough to cover various extreme weather events on the Northern hemisphere at a previously unmatched spatial resolution. Deploying the highly scalable Weather Research and Forecasting (WRF) model on 84,000 compute cores of Hornet, the achieved results confirm an extraordinary quality with respect to the simulation of fine scale meteorological processes and extreme events.

Organic Photovoltaics are a promising thin-film solar cell technology since all the constituting layers can be processed from solution processable materials. In order to improve the efficiency of those solar cells it is necessary to optimize their light trapping ability. Different techniques were evaluated in a research project on SuperMUC of LRZ.

Scientists from the University of Hohenheim (Stuttgart/Germany) aim to investigate and to improve the performance of regional climate simulations in Europe with the Weather Research and Forecast (WRF) model. The model is operated from 12 km down to the convection permitting scale of 3 km, for advancing process understanding.

The flow in the earth's atmosphere involves many complex features. One of these features are so-called gravity waves. They become important as soon as they break somewhere in the atmosphere, since this breaking results in a strong patch of turbulence for no apparent reason. In order to improve the basic understanding of the breaking process, scientists conducted high-resolution simulations of different types of gravity-wave breaking events.

Scientists of the Institute for Hydrodynamics of the Karlsruhe Institute of Technology (KIT) have – for the first time – performed high-fidelity numerical simulations of the formation of sediment patterns in a channel flow configuration.

Using the computing capabilities of HLRS system Hermit, a team of scientists used the Community Earth System Model (CESM) with a strongly eddying ocean submodel to study the presence of ocean eddies on the sensitivity of the Meridional Overturning Circulation (MOC) in the Atlantic Ocean to the Greenland Ice Sheet (GrIS) freshwater anomalies.

A team of scientists of the Technische Universtität München employed an instantaneous steady-state approximation to present steady-state reactivity data from kinetic Monte Carlo (kMC) simulations in the form of an interpolated data field as boundary conditions for the computational fluid dynamics simulation.Their goal was to test the capability of the code in managing complex computational domains, thus allowing for the first time to extend kMC simulations to geometries and conditions relevant to technological applications. 

The cold combustion in fuel cells is a promising alternative energy technology that does not produce greenhouse gases. One of the main problems of solid oxide fuel cells (SOFC) that reduces the efficiency dramatically is the chromium poisoning. The current collectors in SOFCs are made of stainless steel which contains chromium. By chemical reaction chromium can migrate into the porous cathode and react with its surface. This effect degrades the efficiency and has to be controlled.

In past decades, high performance computing has become a valuable tool in many fields of environmental science and technology to utilize computational power for better characterization of the complexity of environmental systems as well as predicting their evolution in time. The challenge is to develop efficient numerical schemes and software implementations which can take full advantage of today’s supercomputing hardware (i.e. PetaFlop platforms). The JUQUEEN project „Massive parallel computation of non-linear multi-field problems in terrestrial systems“ strives to meet this challenge for the solution of thermo-hydro-mechanical-chemical problems in fractured porous media with applications in hydrology, geotechnical engineering and renewable…

Minerals, melts and fluids are the building blocks of our planet Earth. Their formation and alteration are driven by thermodynamics and depend on pressure, temperature and the local availability of chemical elements. Geological processes are especially efficient at high temperatures as prevalent in the Earth's interior and in the presence of melts or (aqueous) fluids. However, direct observations, e.g. by deep drilling, are limited to about 12 km depth. Experimental studies at the extreme conditions of the deeper Earth are challenging and not always easy to interpret. Therefore, a good understanding of what happens beneath our feet can only be obtained by combined efforts from various disciplines of the Earth sciences.

A porous medium is a material characterized by the presence of holes, or “pores“. These pores are usually surrounded by a solid and can be filled with a gas or a liquid. In nature one can find many examples of porous media, such as many types of rock (e.g. in oil reservoirs or aquifers). Many types of man-made porous media exist too, as they can be designed to have very useful properties. For example, porous media form the basis of many types of reactors, filters, or fuel cells.

Supported by the experts of the Leibniz Supercomputing Centre (LRZ), computer scientists, mathematicians, and geophysicists of the Technische Universität München (TUM) and the Ludwig-Maximilians-Universität München (LMU) collectively optimised and completely parallelised the 70,000 lines of code of SeisSol, a software to simulate earth quakes, to optimally leverage the parallel architecture of SuperMUC.

Fusion energy is a very attractive option to provide large-scale and CO2-free electricity production for centuries to come. Here, the goal is to mimic the way the sun generates its power under laboratory conditions on earth. To this aim, one confines a plasma (i.e., an ionized gas), consisting of two heavy versions of hydrogen, namely deuterium and tritium, in a doughnut-shaped magnetic cage and heats it to about 100 million degrees. In order for this to work, however, the energy confinement – which is controlled by turbulent transport – must exceed a certain level. 

Mantle convection is a vital component of the Earth system. The relentless deformation taking place in the mantle by viscous creep has a far greater impact on our planet than might be immediately evident. Immense forces are at work in mantle convection cells: continuously reshaping Earth's surface, the mantle provides the enormous driving forces necessary to support large scale horizontal motion, in the form of plate tectonics and associated earthquake and mountain building activity.

Atmospheric processes and climate change take place on all spatial scales: global, continental down to regional or local scales. Not only do processes on the different scales differ from each other but also regions exhibit various characteristics. Regional and local climate as such depends on small-scale structures such as urbanisation, land use, soil types, water surfaces, orography and vegetation.

Ground shaking due to an earthquake not only depends on the energy radiated at the source but also on propagation effects and amplification due to the response of geological structures. A further step in the assessment of seismic hazard, beyond the evaluation of the earthquake generation potential, requires then a detailed knowledge of the local Earth structure and of its effects on the seismic wave field. 

Whenever we travel by plane, we often experience that the flight becomes bumpy quite suddenly during the descent. This phenomenon causes not only discomfort to the passengers, but also a few headaches to climate scientists, whose models depend critically on properties associated with this phenomenon.

In order to invest in a sustainable energy mix and avoid CO₂ emissions, new energy sources such as fusion energy need to be developed. Understanding turbulent transport is needed for further optimization of fusion reactors but realistic transport time scale simulations of plasma turbulence are computationally very demanding. The aim of the present project is to increase the understanding of the mechanisms behind the sudden improvement in confinement observed in experiments. 

Prediction of turbulence-induced erosion and near-bed transport of sediment particles in turbulent flow is important for many processes in environmental engineering. Beyond its relation to sediment transport, the results of the present study are relevant as well for numerous industrial applications, particularly in the field of process technology, where solid particles are conveyed by a carrier flow. Traditional methods for the prediction of sediment transport are empirical and based on averaged bulk quantities. 

The gas transfer process across the air-water interface plays an important role in many industrial and environmental systems. Very thin diffusive layers mark the interfacial mass transfer of low-diffusive substances. Using simulation technologies, scientists try to achieve a good understanding of the physical processes by resolving the gas transfer in these thin layers.

To study the aerodynamics of vertical axis wind turbines (VAWT) and to carefully characterize the vortex dynamics and decay of VAWT wakes, a team of scientists conducts extensive simulation runs on GCS supercomputers.

The imaging of the Earth‘s interior three-dimensional structure is a prerequisite for the understanding of the mechanisms that drive the continental plates, shape our landscapes, and lead to earthquakes and volcanoes.

Scientists use GCS supercomputers for compute-intensive simulations in order to increase the fidelity of global climate simulations and provide quantitative information about the frequency of high-impact events and their risks. The research activity comprises a large series of global experiments (an ensemble), with each member of the ensemble dynamically simulating 27 years of both current and future climates.

Concerns about the present global energy situation and the impacts of climate change are the driving forces for optimizing combustion power plants operation towards maximum efficiency, and thus minimizing the emission of greenhouse gases. Computational modelling of the combustion process in industrial scale combustion systems has become a key technology to achieve this ambitious goal.