Table of Contents

Subcommittee on Global Change Research, Participating Agencies and Executive Offices

Ad hoc Working Group on Climate Modeling

Foreword

Executive Summary

1. Background

2. Summary of Findings

3. Summary of recommen- dations

4. Final Comments

Charge to the Working Group 

Main Report

1. Purpose

2. Current Situation

3. Scope of Document / Underlying Definitions and Assumptions

4. Elements of Climate Science

5. Issues of Computational Systems

6. Human resources

7. Management / Business Practices / Institutional models

8. Recommen- dations

9. Reference Documents

10. Endnotes

Full Report (PDF)

The continued development and refinement of computational models that can simulate the evolution of the Earth system is critical for the U.S. Global Change Research Program. Such models can be used to look backward to test the consistency of our knowledge of Earth system forcing and response over time periods of interest, and forward for calculating the response of the Earth system to projected future forcing. Models are exceedingly valuable tools for the development of scientific understanding. They also are critical to the environmental assessments used to synthesize Earth science results and provide information to decisionmakers.

Modeling has been an important part of the USGCRP during the last decade. Significant progress has been made in the development and application of atmospheric chemistry, ecosystem, and climate models. However, the U.S. system of distributed centers for modeling and supercomputing has produced both benefits and problems, especially for climate modeling. The system has been very supportive of creative approaches and the use of high-end modeling as a tool for discovery-driven scientific research. But it has not facilitated the development of the kind of product-driven modeling activities that are especially important for making climate model information more usable and applicable to the broader global change research community.

Over the past several years, a number of internal and external analyses have identified significant problems with the U.S. climate modeling effort. A 1998 report by the National Research Council, Capacity of U.S. Climate Modeling to Support Climate Change Assessment Activities (National Academy Press, 1998), concluded that, while the U.S. community is "a world leader in intermediate and smaller climate modeling efforts, it has been less prominent in producing high-end climate modeling results, which have been featured in recent international assessments of the impact of climate change." In the modeling community, the United States has been falling behind several other nations in its ability to perform long-term climate simulations. The NRC report called for a nationally coordinated strategy and greatly improved computing capabilities.

As a step toward defining a U.S. climate modeling strategy, the Environment Division of the White House Office of Science and Technology Policy (OSTP) in January 2000 commissioned an ad hoc Working Group on Climate Modeling Implementation and charged it with preparing a plan for USGCRP climate modeling activities. The Working Group was chaired by Dr. Richard Rood of the National Aeronautics and Space Administration and included a representative from each of the Federal agencies with a significant investment in global weather and climate modeling. Their report and recommendations to the USGCRP are contained in this document.

The USGCRP is in the process of drafting a new long-term Strategic Plan. Parts of the plan will address the issues of modeling capabilities and research on climate variability and change, and will put forth research goals and modeling objectives for the next decade. This report on the development of high-end climate modeling and related computing capabilities raises key issues for the program. We express our gratitude to the Working Group for their important contribution.