Principal Investigator Progress Metric(s)
Objective: The goal of this project is to combine and further develop state-of-the-art versions of an atmospheric general circulation model (AGCM) and oceanic general circulation model (OGCM), and a similarly advanced version of a chemical tracer model (CTM) into a model that describes the coupled global atmosphere-global ocean system including chemical tracers that are found in, and may be exchanged between, the atmosphere and the oceans. The ESM code will have the ability to archive data via a Database Management System (DBMS) and be linked to a system that allows for the remote visualization of model output in real-time. This coupled Earth Systems Model (ESM) will be applied to studies of climate change and ozone depletion.
Approach: The ESM consists of three major elements named above: an AGCM, an OGCM and a CTM. Parallel versions of each of these model codes are being developed and optimized. After parallelization of the individual codes is complete, the different modules will be coupled according to a strategy currently being developed. The software for on-line distributed application management and data visualization will be developed and upgraded throughout.
Accomplishments: The parallelized version of the AGCM (AGCMp) code has been ported to a variety of computer platforms and timings have been obtained. The code achieves a performance of approximately 500 MFLOPS in 128 processors of a CRAY T3D. A parallel version of the OGCM (OGCMp) has been developed and achieves a performance of 670 MFLOPS in 256 processors of an Intel Paragon. The machine architectures supported by the parallel version of the OGCM are the Intel Delta and Paragon. The Hermes communication system was developed, which is a prototype system for on-line distributed application management. The HERMES system allows researchers to determine the state of remotely executing applications by allowing interactive acquisition and visualization of output datasets as they are produced. Code has been developed that interfaces Hermes and the Postgres DBMS, both as a transmitter and recipient of data and a schema for AGCM output was created.
Significance: GCMs that describe atmospheric and oceanic dynamics play a key role in the study of climate and climate change. Examples of outstanding problems that may be addressed with coupled atmosphereocean GCMs are El Niûo Southern Oscillation (ENSO) events and the role of oceans in moderating the greenhouse warming effect of carbon dioxide and other gases. Chemical tracer models describe that detailed composition of the atmosphere, couple chemical and climate processes, and simulate the behavior of the ozone layer. Such a chemical/aerosol tracer model can be driven by an AGCM to investigate a wide range of problems such as the formation of the Antarctic "ozone hole" and the impact of volcanic eruptions on the ozone layer and global climate.
Status/Plans: Development of a parallel version of the CTM is nearly complete; verification and timings of the code are soon to be performed. Optimization of the AGCMp code on the CRAY T3D and IBM SP1/2 is underway. Porting of the OGCMp code to architectures other than Intel will soon begin. Coupling of the CTM with the OGCM has begun. The Hermes system is being updated from the prototype version 1.0 to a fully-featured version 2.0. Methods to optimize the system for the archival and retrieval of model data using DBMSs are currently being evaluated. The extension of the schema for AGCM output to include output from the other modules will begin shortly.
Principal Investigator Progress Metric(s)
Point of Contact:
Return to the PREVIOUS PAGEcurator: Larry Picha (lpicha@cesdis.gsfc.nasa.gov)