The nation's collection of climate models should advance substantially to deliver more detailed, smaller scale climate projections, says a new report from the National Research Council. To meet this need, the report calls for these assorted climate models to take a more integrated path and use a common software infrastructure while adding regional detail, new simulation capabilities, and new approaches for collaborating with their user community.

From farmers deciding which crops to plant next season, to mayors preparing for possible heat waves, to insurance companies assessing future flood risks, an array of stakeholders from the public and private sectors rely on and use climate information. With changes in climate and weather, however, past weather data are no longer adequate predictors of future extremes.

Advanced modeling capabilities could potentially provide useful predictions and projections of extreme environments, said the committee that wrote the report. Over the past several decades, enormous advances have been made in developing reliable climate models, but significant progress is still required to deliver climate information at local scales that users desire.

The U.S. climate modeling community is diverse, including several large global efforts and many smaller regional efforts. This diversity allows multiple research groups to tackle complex modeling problems in parallel, enabling rapid progress, but it also leads to some duplication of efforts.

The committee said that to make more efficient and rapid progress in climate modeling, different groups should continue to pursue their own methodologies while evolving to work within a common nationally adopted modeling framework that shares software, data standards and tools, and model components.

"Climate models are computationally intensive and among the most sophisticated simulation tools developed, and the 'what if' questions they help solve involve a mind-boggling number of connected systems," said committee chair Chris Bretherton, a professor in the departments of atmospheric science and applied mathematics at the University of Washington, Seattle.

"Although progress will likely be gradual, designing the next generation of models will require us to move toward unification and work more closely with the user, academic, and international communities."

The committee identified a multipart strategy consisting of various efforts over the next two decades to advance the nation's climate modeling endeavor. One such effort is the climate modeling community working toward a shared software infrastructure for building, configuring, running, and analyzing climate models that could help scientists navigate the imminent transition to more complex supercomputing hardware. This would enable scientists to compare and interchange climate model components, such as land surface or ocean models.

Additional steps include convening an annual forum for national climate modeling groups and users to promote tighter coordination and allow more efficient evaluation of models; nurturing a unified weather-climate modeling effort that better exploits the synergies among weather forecasting, data assimilation, and climate modeling; and developing a training program for "climate model interpreters" who could serve as an interface between modeling advances and user needs.

In addition, the committee emphasized that the country should enhance ongoing efforts to:

+ sustain state-of-the-art computing systems for climate modeling;

+ continue contributing to a strong international climate observing system capable of characterizing long-term climate trends and climate variability;

+ develop a training and reward system that entices talented computer and climate scientists into climate model development;

+ improve the IT infrastructure that supports climate modeling data sharing and distribution; and

+ pursue advances in climate science and uncertainty research.

The National Research Council, the operating arm of the National Academy of Sciences and National Academy of Engineering, is an independent, nonprofit institution that provides science and technology advice under a congressional charter granted to the NAS in 1863. A committee roster follows.