Learn More
The Community Climate System Model (CCSM) is a computer model for simulating the Earth's climate. The CCSM is built from four individual component models for the atmosphere, ocean, land surface, and sea ice. The notion of a physical/dynamical component of the climate system translates directly to the software component structure. Software design of the CCSM(More)
Generating credible climate change and extremes projections remains a high-priority challenge, especially since recent observed emissions are above the worst-case scenario. Bias and uncertainty analyses of ensemble simulations from a global earth systems model show increased warming and more intense heat waves combined with greater uncertainty and large(More)
We describe the design of a parallel global atmospheric circulation model, PCCM2. This parallel model is functionally equivalent to the National Center for Atmospheric Research's Community Climate Model, CCM2, but is struc-tured to exploit distributed memory multicomputers. PCCM2 incorporates parallel spectral transform, semi-Lagrangian transport, and load(More)
The spectral transform method is a widely-used numerical technique for solving partial diierential equations on the sphere in global climate modeling. This paper describes the parallelization and performance of the spectral method for solving the nonlinear shallow water equations on the surface of a sphere using a 128-node Intel iPSC/860 hypercube. Solving(More)
The spectral transform method is a standard numerical technique used to solve partial diierential equations on the sphere in global climate modeling. In particular, it is used in CCM1 and CCM2, the Community Climate Models developed at the National Center for Atmospheric Research. This paper describes initial experiences in parallelizing a program that uses(More)
We present a scalable parallel Strassen's matrix multiplication algorithm for distributed-memory, message-passing computers. Strassen's algorithm to multiply two N x N matrices reduces the asymptotic operation count from O(N3) of the traditional algorithm to O(N2.*1). In a sequential implementation the Strassen's algorithm offers better performance even for(More)
Earth system and environmental models present the scientist/programmer with multiple challenges in software design, development, and maintenance, overall system integration, and performance. We describe how work in the industrial sector of software engineering—namely component-based software engineering—can be brought to bear to address issues of software(More)
Community models for global climate research, such as the Community Atmospheric Model, must perform well on a variety of computing systems. Supporting diverse research interests, these computationally demanding models must be efficient for a range of problem sizes and processor counts. In this paper we describe the data structures and associated(More)
Cartesian coordinates are used to solve the nonlinear shallow-water equations on the sphere. The two-dimensional equations, in spherical coordinates, are first embedded in a three-dimensional system in a manner that preserves solutions of the two-dimensional system. Solutions of the three-dimensional system, with appropriate initial conditions, also solve(More)
1. INTRODUCTION The Computer Hardware, Advanced Mathematics , and Model Physics (CHAMMP) program (Department of Energy 1990) seeks to provide climate researchers with an advanced mod-eling capability for the study of global change issues. Current general circulation models are usually applied at coarse spatial resolution with minimal coupling between ocean,(More)