The model used by DWD is named COSMO and is the same being used in Switzerland and other countries in Europe and worldwide. COSMO has been developed in the late 90thies as a non hydrostatic regional model. COSMO is not only being used by weather services but also by the academia for research and to teach and train students . DWD and Ueli Schättler are also involved in the Swiss HP2C project aimed to port COSMO to next generation HPC platforms.

At this place we would also like to remember you about the Colloquium at MeteoSwiss on How much HPC does meteorology need? planned for tomorrow, Tuesday, November 29th.

The successful candidate will participate in several of the focus areas of the HP2C project:

• Contribute towards the implementation of a domain specific embedded language (DSEL) based stencil library (C++) and its application in a weather and climate code.
• Explore possibilities of using CPU-GPU-type heterogeneous architectures for speeding up portions of a weather and climate code.
• Redesign of the I/O workflow and implementation into order to achieve scalable and efficient I/O on massively parallel architectures.
• Present and publish results in high quality refereed conferences and journals.

The candidate should meet the following requirements:

• BS/MS/PhD in Computer Science/Engineering or equivalent work experience
• Strong experience with OO-programming in C++
• Working knowledge of parallel programming languages and systems
• Team player
• Solution oriented
• Fluency (written and oral) in English

Any of following skills are not required but will be considered an advantage:

• Experience in parallel I/O
• Background in High Performance Computing
• Experience in GPU programming

This position is an opportunity to both shape and participate in a high-risk/high-payoff software development project at the leading-edge of high performance computing and gain insight into climate and weather modeling. The position is based at C2SM/ETH Zurich but frequent exchange with and travels to project partners at MeteoSwiss (Zurich), CSCS (Lugano), SCS (Zurich) and DWD (Offenbach, Germany) will be required. C2SM and the partners institutions involved in the project provide excellent working conditions in a stimulating and collaborative team of highly motivated researchers and PhD students.

Potential applicants seeking further information are invited to contact Isabelle Bey at C2SM (isabelle.bey(at)env.ethz.ch, +41 44 632 79 15) or Oliver Fuhrer at MeteoSwiss (oliver.fuhrer(at)meteoswiss.ch, phone +41 44 256 93 59). The applications including a CV, a statement of interest, and addresses of two referees should be sent by email to Isabelle Bey (isabelle.bey(at)env.ethz.ch). Applications received before May 1st, 2011 will receive full consideration. The position will remain open until filled.

Abstract

We consider regularization methods for the nonconvex unconstrained and convexely constrained optimization problems.  After motivating these algorithms, we review known convergence results and emphasize their remarkabke complexity properties, that is the number of function evaluations that are needed for the algorithm to produce an epsilon-critical point.  We also discuss the complexity of the well-known steepest-descent and Newton’s method in the unconstrained case and report some surprising conclusions regarding their relative complexity.

Bio

Philippe Toint is director of the  Department of Mathematics of the University of Namur (Belgium), co-director of the  Numerical Analysis Research Unit, director of the  Transportation Research Group. Chairman elect (2010-2012) of the Mathematical Optimization Society , SIAM fellow (class 2009) and Honorary Professor at the University of Edinburgh.

His research interests are smooth nonlinear optimization, with an emphasis on the algorithmic viewpoint, ranging from convergence theory to numerical considerations and software development ( LANCELOT, CUTEr, GALAHAD ). Practical and multidisciplinary applications of optimization techniques.

Multiple scales analyses and numerics for atmospheric flows

Regime(s) of validity of sound-proof models

Abstract

Asymptotic techniques generalize the classical approach of scale analysis in theoretical meteorology. Through, e.g., matched asymptotic and multiple scales expansions they allow us to systematically study interactions across separated length and times scales. This will be demonstrated drawing from recent work on hurricane-like concentrated vortices and on cloud–internal wave interactions.

Whereas the classical theory of anelastic mostions by Ogura and Phillips (1962) is naturally captured in an asymptotics-based framework, its subsequent extensions, e.g., by Dutton & Fichtl (1969), Lipps & Hemler (1982), Bannon (1996), as well as Durran’s pseudo-incompressible model (1989,2008) pose a particular challenge. I will show that their systematic theoretical justification will require techniques that go beyond scale analysis and single or multiple scales expansions.

From these analytical developments one can draw a series of conclusions regarding the construction of robust numerical method for atmospheric flow simulations. The last part of the lecture will highlight how multiscale asymptotics ideas may be combined with numerical multigrid techniques to generate a novel scale-dependent time integration scheme for weakly compressible flows.

BIO

Rupert Klein holds a professorship for “Scientific Computing/Modelling and Simulation of Global Environment Systems” at the Institute for Mathematics and Computer Science at the Freie Universität Berlin. His research is characterised by the merger of applied mathematical modelling and modern computational techniques. During his 20-year academic career he has addressed problems in theoretical and computational fluid mechanics, ranging from high-speed and low-speed combustion, via the dynamics of slender vortices, to multiplescale phenomena in atmospheric flows.

Dr. Klein was born in Wuppertal, Germany, and studied Mechanical Engineering at RWTH Aachen, Germany, where he also received his doctoral degree in 1988. A two-year postdoctoral research fellowship with the Program in Applied and Computational Mathematics at Princeton University, USA, was followed by an assistant professorship with the Department of Mechanical Engineering of RWTH Aachen, Germany. His interest in environmental problems and in man-environment-machine systems led to a professorship with the department of Safety-Technology at Wuppertal University in 1995. Soon afterwards he was jointly appointed by the Potsdam Institute for Climate Impact Research, where he then headed the Data & Computation Department, and Freie Universität Berlin. This appointment placed him at the interface between climate research and modern applied and computational mathematics. In 2007 he joined the Department of Mathematics and Computer Science with a full-time appointment.

Klein was awarded the Horning Memorial Award and the Arch T Colwell Merit Award from the Society of Automotive Engineers (SAE) in 1990, the Bennigsen–Förder Prize from the state of North-Rhine-Westphalia in 1995, and the International Fellow Award from Johns Hopkins University in 1995/96. More recently he was awarded the Gottfried-Wilhelm-Leibniz-Preis of the Deutscheforschungsgemeinschaft, and became a member of the Berlin-Brandenburg Academy of Sciences. Currently, he is a member of the editorial boards of Theoretical and Computational Fluid Dynamics, Computers and Fluids, and Communications in Applied Mathematics and Computational Science.

(Cross posting from ETH Life)

The Swiss platform for High-Performance and High-Productivity Computing (HP2C) is the world’s first and only project with the aim of developing optimized scientific simulations for high-performance computers. Seismologists from ETH Zurich are also involved, namely in the «Petaquake» project.

What is the exact structure of the Earth’s interior? What are the processes that take place there? Where and how do earthquakes originate? These are some of the central questions concerning our planet that we have not yet been able to answer with certainty. A view into the Earth’s interior similar to computed tomography for a human being could provide these answers, thus helping to improve seismic risk maps. This would be an important basis for assessing the risk of the locations of nuclear power plants or hospitals in Switzerland for example.

Rread the full article on ETH Life »

These projects should focus on advances in mathematical methods, algorithms and computational techniques to better exploit next generation supercomputing platforms for the analysis and forecast of global challenges, including climate change, regional weather prediction, natural hazards, but also social challenges like major disruptions in financial markets. Given the short duration and the limitation of budget, projects are expected to focus on methodological development and testing to prove the feasibility and impact of the new methods proposed. Projects focused merely on methods and algorithms for current low-end computer platforms will not be supported.

Projects will be developed by one or more groups in a Swiss higher education institution, in close cooperation with the HP2C core group at CSCS and USI, which will provide scientific computing expertise (computational mathematics and computer science). The application developers from the project will also have access to the prototype computing hardware operated and maintained at CSCS.

Applicants are requested to notify their intention to submit an application by August 31, 2010. Complete project proposals must be submitted by September 15, 2010.

Additional information »

In December 2009, the steering committee of HP2C selected the following 8 projects to be supported:

• Advanced Gyrokinetic – Advanced gyrokinetic numerical simulations of turbulence in fusion plasmas; Prof. Laurent Villard, EPF Lausanne
• CP2K – New Frontiers in ab initio Molecular Dynamics; Prof. Dr. Juerg Hutter, Uni Zürich
• Computational Cosmology Computational Cosmology on the Petascale; Prof. Dr. George Lake, Uni Zürich
• Selectome – Selectome, looking for Darwinian evolution in the tree of life; Prof. Dr. Marc Robinson-Rechavi, Uni Lausanne
• Cardiovascular System – HPC for Cardiovascular System Simulations; Prof. Alfio Quarteroni, EPFL
• MAQUIS – Modern Algorithms for Quantum Interacting Systems; Prof. Thierry Giamarchi, University of Geneva
• PETAQUAKE – Large-Scale Parallel Nonlinear Optimization for High Resolution 3D-Seismic Imaging; Dr. Olaf Schenk, Uni Basel
• Stellar Explosions – Productive 3D Models of Stellar Explosions; Dr. Matthias Liebendörfer, Uni Basel

A decision about 4 additional projects is expected in the next weeks.

For additional information about HP2C and its projects see »

Cray press release »