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 United States requires the capability to deliver state-of-the-art products for weather forecasting, seasonal-to-interannual predictions, and climate assessments in order to answer policy-relevant questions in a timely and efficient way. This includes the development of model and data systems that provide the best possible direct information on how environmental factors impact the U.S. and its assets, as well as evaluation of the relationship of the country's regional environment to global environmental processes.

This report will outline an approach for the U.S. to develop a high-end climate modeling capability to address the strategic interests of the Nation. These interests range from the benefits that would be received by improved model predictions of weather and seasonal characteristics to the increasing use of environmental assessments in the determination of regional and global policies. It is critical that U.S. policy makers have at their access the ability to best evaluate, for example, the impact that changes in the emission of a particular greenhouse gas might have on U.S. interests. Such a calculation must be timely to a particular deliberation and would require an ensemble of comprehensive scenarios to be run and evaluated in a matter of months. Presently, this calculation would require a number of years. Since several other countries have the capability to make these assessments at a rate many times faster than the U.S., the U.S. is at a strategic disadvantage. A number of shortcomings in the U.S. approach to achieving a high-end climate science capability are documented in the report Capacity of U.S. Climate Modeling to Support Climate Change Assessment Activities (National Academy Press, 1998). These shortcomings are tangibly indicated by the U.S. National Assessment, which relies on results of Canadian and British models because no U.S. model met the criteria established for inclusion in the assessment.[1]

Our report first provides the context of the current state of climate-science in the U.S. and then identifies a number of key issues that must be faced if the U.S. is to develop a climate service with a credible high-end modeling capability. We assert that a capability that is state-of-the-art, comparable to the best in the world, is in the best interest of the Nation. Therefore, evaluation of U.S. capabilities relative to those of other countries is an important metric of success. We then subdivide climate-science research activities, distinguishing between discovery-driven and product-driven research and defining high-end modeling. After stating the need to build a product-driven climate service, we explore the issues that must be addressed to build this service by first splitting climate-science into three Elements: Modeling, Data, and Computational Systems. These Elements should not, however, be treated separately, and we discuss the need for integration across these Elements as well as across traditionally separated disciplines such as weather forecasting, seasonal prediction, data assimilation, atmospheric chemistry, and coupled climate modeling. Following that, the software and hardware aspects of computational systems are discussed. Then issues of human resources and the characteristics of an institution to deliver the required climate-science products are presented and concluded to be as challenging and important as any scientific and technical issues that confront the field. Finally, general guidelines for investment and management strategies are made.