
Current Research ProjectsThe Model Coupling ToolkitI colead the development of the Model Coupling Toolkit (MCT). MCT is a set of software tools for coupling messagepassing parallel models to create a parallel coupled model. MCT provides the following core coupling services: a component model registry; domain decomposition descriptors; communications schedulers for parallel intercomponent data transfer and intracomponent data redistribution; a flexible and indexible (i.e., randomaccess) field data storage datatype; a time averaging and accumulation buffer datatype; a general spatial grid representation capaple of supporting unstructured grids; parallel tools for intergrid interpolation implemented as matrixvector multiplication; spatial integration and averaging tools (including paired integrals to support conservative interpolation); and tools for merging data from multiple components for use by another component. You can learn more about MCT from our Web Site. Design and Development of a Terascale Community Climate System Model This is a joint DOENSF project focused on the software and scientific development of CCSM. DOE funding comes from the Scientific Discovery through Advanced Computing (SciDAC) initiative. The three major goals are 1) increasing model performance (in particular throughput) to enable longer simulations, 2) improvement of the overall software quality of the model to make it easier to maintain and extend, and 3) addition of new processes (e.g., atmospheric chemistry and biogeochemistry). Argonne's major contribution to this effort has been the design and development of a modular, distributedmemory, highperformance flux coupler. This new coupler is built on top of a software package called the Model Coupling Toolkit. Common Component Architecture (CCA) Forum DOE laboratories have long led the charge to create opensource software to support rapid development of scientific simulation applications. In the past, these efforts have produced numerical libraries and toolkits (for example the Portable Extensible Toolkit for Scientific computation (PETSc)). DOE has also suported the development of software frameworks, which are languageindependent software environments for building componentbased applications. The Common Component Architecture Forum seeks to define a universal software framework for simulation software. The main manifestation of CCA is the DOE SciDACfunded Center for Component Technology for Terascale Simulation Software. My main role in CCA is climate applications lead. Earth System Modeling Framework (ESMF) Project NASA's Earth System Technology
OfficeComputational Technology (ESTOCT, formerly HPCC) is devoting substantial
funding towards the development of a software framework for use by the
climate modeling and weather forecasting communities. This software
framework has been dubbed the Earth System Modeloing Framework (ESMF),
and I am a coinvestigator on the proposal for the framework core.
More information about ESMF can be found here.
Past ProjectsPhysicalspace Statistical Analysis System (PSAS)From 19961999 I worked for NASA's Data Assimilation Office (DAO) and the Meteorology Department / Earth System Science Interdisciplinary Center (ESSIC) at the University of Maryland. During this time I worked on various parts of their GEOS Data Assimilation System. Most notably, I helped build their online data quality control (QC) system, and participated in the ongoing development of the Physicalspace Statistical Analysis System (PSAS), and its messagepassing parallel version MPPSAS. Just so you know, PSAS is pronounced pizzaz. Documentation of the PhysicalSpace Statistical Analysis System (PSAS) Part II: The FactoredOperator Formulation of Error Covariances; J. Guo, J. W. Larson, G. Gaspari, A. da Silva, and P. M. Lyster, 1998: DAO Office Note 9804 (download a postscript file). Documentation of the PhysicalSpace Statistical Analysis System (PSAS) Part III: The Software Implementation of the PSAS; J. W. Larson, J. Guo, G. Gaspari, A. da Silva, and P. M. Lyster, 1998: DAO Office Note 9805 (download a postscript file). Description of the Software Implementation of the PSAS, Slides from my presentation at the HPCC PSAS Workshop, October 26, 1998. A glossary of terms found in the above slides. My Less Recent PastFrom 19921996 I was a postdoctoral fellow at Macquarie University, and then at the Australian National University. During my time at Macquarie, I was involved in the Model Evaluation Consortium for Climate Assessment (MECCAthis was the forerunner to ACACIA). At ANU, worked in the Centre for Resource and Environmental Studies on regional and global climate issues. I also worked with computer scientists in the Department of Computer Science and the ANU Supercomputer Facility on porting of parallel regional and global weather models to Fujitsu supercomputers.My Student DaysI started my career as a theoretical physicist. During my student days I did research in soliton theory and in integrability of dynamical systemsbasically lots of penandpaper stuff. My work in soliton theory demonstrated the applicability of the focusing nonlinear Schroedinger (NLS) equation as a complete envelope theory for the sineGordon equation. My dissertation work concerned the integrability of charged particle dynamics in the Earth's magnetotail region (and in particular dynamics in neutral sheet and neutralline magnetic/electric field combinations). I was able to prove that charged particle dynamics in the neutral sheet configuration were integrable in terms of the second Painleve transcendent. While working on my dissertation, I did a lot of symbolic computation using Mathematica, and also wrote my own particlepusher code to perform numerical studies to confirm my analytical results.Professional Societies of which I am a Member American
Geophysical Union
About the Painting at the Top of This PageIt is entitled "Campus Lunch at W & M," and was painted by my uncle Robert Kilbride.

