1 / 26

Donald Dabdub University of California, Irvine International Aerosol Modeling Algorithms Davis, CA December 6, 2007

melanie
Download Presentation

Donald Dabdub University of California, Irvine International Aerosol Modeling Algorithms Davis, CA December 6, 2007

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

    1. Donald Dabdub University of California, Irvine International Aerosol Modeling Algorithms Davis, CA December 6, 2007

    3. Intel Touchstone Delta One of the few computers to sit significantly above the curve of Moore's Law. Caltech, 1991 Based around the i860 RISC microprocessor.

    4. CM5 MIT, 1991. Danny Hillis and Sheryl Handler Had as many as 65,536 processors SuperSPARCs chips

    5. GigaBUSTER Switzerland, 1992 1.6 GFlops peak performance Standard Digital UNIX environment Distributed memory architecture MPI (Message Passing Interface) ICI (Intelligent Communication Interface) Workstation Cluster and Parallel Computer in one Up to 1 GByte memory Up to 45 GBytes internal disk storage Only 500 W power consumption

    10. Today’s Computing Resources

    12. The Air Quality Models Meteorological Conditions: Measurements from Southern California Air Quality Study (SCAQS), Sept. 27-29, 1987 High ozone concentration episode due to strong thermal inversion and wind circulation The CIT Airshed model is based on the numerical solution of the atmospheric diffusion equation in a grid of 994 columns with 5 vertical layers of variable height. The equation includes advective transport, sources and sinks, such as area or point emissions and dry deposition, chemical production/losses and size-resolved and chemically-resolved aerosol formation. Meteorological conditions were obtained by processing the measurements acquired during the SACQS (Southern California Air Quality Study), in Sept. 27-29. During this period, a complete set of meteorological data was compiled. These measurements encompass temperature field, wind field, uv radiation field, and information of the terrain such as surface roughness to calculate deposition velocities, etc… The chemical Mechanism is the LCC mechanism, and it includes 121 reactions, with 47 gas species and 19 aerosol species partitioned into 8 different size bins. The CIT Airshed model is based on the numerical solution of the atmospheric diffusion equation in a grid of 994 columns with 5 vertical layers of variable height. The equation includes advective transport, sources and sinks, such as area or point emissions and dry deposition, chemical production/losses and size-resolved and chemically-resolved aerosol formation. Meteorological conditions were obtained by processing the measurements acquired during the SACQS (Southern California Air Quality Study), in Sept. 27-29. During this period, a complete set of meteorological data was compiled. These measurements encompass temperature field, wind field, uv radiation field, and information of the terrain such as surface roughness to calculate deposition velocities, etc… The chemical Mechanism is the LCC mechanism, and it includes 121 reactions, with 47 gas species and 19 aerosol species partitioned into 8 different size bins.

    13. Sequential Data Flow

    14. Main Algorithms

    15. Concurrent I/O Data Flow

    16. First Steps Parallelizing the chemistry on 8 nodes of the Alliant FX/8. Speedup=2.5 (Shin and Carmichael, 1992) Parallelizing the chemistry and transport on 128 nodes of the Intel Touchstone Delta. Speedup=30 (Dabdub and Seinfeld, 1994) Parallelizing the chemistry, transport and I/O on 256 nodes of the Intel Paragon. Speedup=94.5 (Dabdub and Seinfeld, 1995)

    22. Current work Performing long term (e.g. a year) of air quality simulations (Winner) Relaxing the aerosol internally mixed approximation. (Kleeman) Implementing parallel plume in grid computations. (Karamchandani) Using highly detailed emission inventories. (Tahgavi, Cautenet, Arteta)

    23. A New Paradigm

    24. Conclusions Parallel computers allow atmospheric scientists to enlarge the class of problems that can be successfully handled: Higher Resolution Longer Simulations More Comprehensive Physics and Chemistry Faster Results

    25. Future Questions How to implement model when ~O(10,000) processors are available? How to best take advantage of heterogeneous computer networks? (The grid) How to couple different type of models?

    26. Acknowledgements California Air Resources Board Prof. Rajith Manohar Dr. Ajith Kaduwela The CES Lab

More Related