The National Academies of Sciences, Engineering and Medicine
Office of Congressional and government Affairs
At A Glance
: Energy Policy Reauthorization
: 03/30/2000
Session: 106th Congress (Second Session)
: Elbert W. Friday Jr.

Director, Board on Atmospheric Sciences and Climate, Commission on Geosciences, Environment, and Resources, National Research Council

: Senate
: Committee on Energy and Natural Resources




March 30, 2000


Thank you for this opportunity to discuss with you certain issues relating to the U. S. Global Change Research Program (USGCRP). This is one of our nation’s most important scientific efforts, seeking to understand more about the planet on which we live and how it changes. The USGCRP began in 1989, and was codified by the Global Change Research Act of 1990.

As a part of the enabling legislation for the USGCRP, the National Research Council (NRC) was charged with recommending priorities for future global change research, drawing from information obtained from domestic and international sources. The NRC report, Global Environmental Change: Research Pathways for the Next Decade (hereafter referred to as the Pathways Report), represents the most recent of many reviews of global change research by the NRC. It provides a comprehensive review of the USGCRP by the NRC and makes a number of recommendations for the future of the program and the elaboration of a ten-year plan by the USGCRP agencies. In today's testimony I will describe the conclusions and recommendations from the Pathways Report and also briefly discuss three other important NRC reports covering key aspects of the USGCRP. These are: Capacity of U S Climate Modeling to Support Climate Change Assessment Activities, (hereafter referred to as the Modeling Report), Adequacy of Climate Observing Systems, (hereafter referred to as the Observing System Report), and Reconciling Observations of Global Temperature Change, (hereafter referred to as the Reconciling Temperature Report).

Overall Review of the USGCRP contained in the Pathways Report

The Pathways Report represents a comprehensive review of the results of a decade of the USGCRP’s research-related investments leading to significant advancements in our understanding of the Earth’s ever changing physical, chemical, and biological systems and the growing human influences on these systems. It also provides recommendations to the federal agencies for focusing attention on critical unanswered scientific questions that must be resolved to fully understand and usefully predict global change, and ensuring that scientific knowledge can guide and respond to policies. In reviewing the past contributions of the USGCRP, the report calls attention to a key set of "lessons learned" –attributes that the Program must maintain and precepts it must observe to achieve future success. These include the following needs: programmatic focus to overcome the disaggregation of the national effort across multiple agencies; balance among observing systems, data systems, and research and analysis; maintaining critical observations and institutionalizing critical measurement systems in an operational mode; well-calibrated observations; and finally, a more focused scientific strategy.

The report contains a detailed analysis of the major scientific areas of global change research and identifies the scientific challenges that need to be addressed by the USGCRP. These are too numerous and too detailed to be included in this testimony, but I would like to provide several excerpts from the Findings and Recommendations chapter of the report.

The first recommendation dealt with the research program:

"Recommendation 1: Research priorities and resource allocations must be reassessed, with the objective of tying available resources directly to the major unanswered Scientific Questions identified in this report. The USGCRP's research strategy should be centered on sharply defined and effectively executed programs and should recognize the essential need for focused observations, both space-based and in situ, to test scientific hypotheses and document change."

The report offers detailed guidance on central scientific issues and research questions in 6 topical themes, including:

• - changes in the biology and biogeochemistry of ecosystems,

• - changes in the climate system on season to interannual time scales,

• - changes in the climate system on decade-to-century time scales,

• - changes in the chemistry of the atmosphere,

• - paleoclimate, and

• - human dimensions of global environmental change.

In reviewing the past investments in the science program, it notes that resources have been most effectively utilized when applied in ways that: strengthen the link between primary unanswered questions and the nation’s intellectual resources, improve the potential for technical innovations, provide educational and public outreach opportunities, and serve the vital information needs of decision makers

The report goes on to discuss the importance of research concerning global change process studies:

"Elucidating the climate system and possible anthropogenic changes, in addition to natural variability, is a paramount goal in these studies. A satisfactory demonstration of secular trends in the Earth’s climate system, for example, requires analysis at the forefront of science and statistical analysis. Model predictions have been available for decades, but a clear demonstration of their validity, a demonstration that will convince a reasoned critic on cross examination, is not yet available. This is not in itself either a statement of failure or a significant surprise. Rather, it is a measure of the intellectual depth of the problem and the need for carefully orchestrated, long-term observations."

The report addresses several aspects of the needs for observing systems, including the importance for understanding several key crosscutting themes:

"Recommendation 2: Following on Recommendation 1, the national strategy of the USGCRP for Earth observations must be restructured and must be driven by the key unanswered Scientific Questions. Observational capability must be developed to support research addressing critical common themes within these scientific elements. Foremost among these themes are the following:

• understanding the Earth's carbon and water cycles;

• characterizing climate change, including the human dimensions component, on temporal and spatial scales relevant to human activities;

• and elucidating the links among radiation, dynamics, chemistry, and climate."

The report identifies one of the recurring themes with respect to the observing system:

"The critical nature of high-quality observations to the scientific and public policy issues posed by global environmental change places demands and constraints on whatever path a USGCRP observational strategy attempts to chart; however, a specific, well-considered, and realistic strategy, including costs and schedule, for obtaining the observations of past, present, and future expressions of global environmental change is essential. The strategy will need an effective institutional mechanism for implementation. As an example, no agency currently has the responsibility for carrying out or coordinating a comprehensive program of climate observations."

The report goes on to stress the need for a coherent observation strategy:

"Recommendation 3: The strategy for obtaining long-term observations designed to define the magnitude and character of Earth system change must be reassessed. Priority must be given to identifying and obtaining accurate data on key variables carefully selected in view of the most critical Scientific Questions and practically feasible measurement capabilities."

"The strategy must take the following into account:

• The fact that observing systems have been designed for purposes other than long-term accuracy and that this has undercut the long-term calibration needed for scientific understanding of global change

• The overall balance and innovative treatment of observations: the balance between space-based observations and in situ observations, between operational and research observational systems, and between observations and analysis

• The gaps between research and operational observational systems that could threaten needed long-term records

• The end-to-end responsibility and the principal investigator mode for research observational systems."

The Pathways Report recognized the need for technological innovation to address the complex observational problems:

"Recommendation 4: The restructured national strategy for Earth observations must more aggressively employ technical innovation. Because of fixed budgets, resources should be reallocated from the large, amalgamated space-based approach to a more agile, responsive ensemble of observations. This goal will require carefully placed investments in new technologies. Technological advances in small satellite systems, robotics, microelectronics, and materials must be exploited to establish a sound balance between in situ ground/ocean-based, airborne, and space-based observations. Innovative treatment of the nation's research aircraft capability, piloted and robotic, is strongly advised. The research and analysis (R&A) component of the national research effort must be recognized for its central contributions to science, public policy, and understanding human dimensions issues."

The report stresses that the need for information is really the driving force of the USGCRP. This includes communication of the fundamentals of the science and policy issues as well assuring ready access to the scientific data:

"Ultimately, the USGCRP is about information. Information must flow within the program and also to the broad community of users. The subject of the program’s research demands that information flow effectively to the public at large as well as to researchers. This is an important issue, and it should not be ignored by either the community of scientists engaged in global change research or the agencies that support this research with public funds."

"Recommendation 5: The USGCRP must revitalize its strategy for the data systems used for global change research. Emphasis must be placed on designing and selecting flexible and innovative systems that appropriately reflect focused responsibility for data character, that provide open access to the scientific community and the public, and that rapidly evolve to exploit technological developments."

The report stresses the importance of models in understanding the complex interactions of the various elements of global change. The identification of the need to be able to provide decision-makers with predictions included the following discussion:

"As mandated by its implementing legislation, the USGCRP seeks to provide useful information to the policy process. A direct implication of this responsibility is that the information must be scientifically credible, that it be of genuine interest and value, and that, to the greatest extent possible, it provide lead time for policy action. The last requirement implies provision of some prognostic information. This requirement does not necessarily entail a "prediction," but it does raise the same concerns as any prediction or predictive process. These concerns revolve around general, and not necessarily scientific, issues such as usefulness, trustworthiness, and credibility of the information. In general, a model or a set of models will often be at the center of the predictive process."

"Finding 6: The policy issues that confront global change research, like the Scientific Questions, are serious, particularly with regard to their impact on humans. These issues will rely on models of exceedingly complex behaviors over a significant range of scales in space and time. Significant challenges face the scientific community in the form of many and various modeling issues, from initialization to validation. Important, unsolved, and difficult problems remain for formulating useful prognostic models over a range of topics in human dimensions research. Advances in developing and most importantly in testing and evaluating models are needed. The United States is no longer in the lead in this critical field."

"The fact that the United States is no longer in the lead in applying global models is not purely a statement of criticism. Strong scientific work, particularly in the area of modeling, has been advancing around the world. This is to be applauded. Global change research, particularly in the area of prognostic activities, requires a full suite of models to adequately bracket the complex problems that the USGCRP seeks to address. Thus, advances in modeling capabilities in other parts of the world are of significant benefit to the USGCRP. Testing adequately complex models is very computing intensive, and if computing resources are not adequate and available, then there is clearly the danger that the dynamical aspect of models will not be sufficiently understood and hence that the models will be misapplied. Currently, the potential exists that the advanced models built in the United States cannot (or will not) be adequately tested and properly applied to key problems, such as national and regional expressions of transient climate variability and change because of a lack of available computing resources. The United States must apply greater resources, particularly (but not exclusively) in the area of advanced computing machines. National boundaries should not influence where machines are purchased."

"Recommendation 6: The USGCRP must foster the development and application of models at the scales of time and space needed to understand and project the specific mechanisms controlling changes in the state of the Earth system, thus providing the information required to support important policy processes. The USGCRP must give increased emphasis to models that treat multiple stresses on systems; it must therefore secure adequate computing resources so that large scale, complex models can be rigorously tested under multiple forcings."

"Models must be tested and evaluated with observations. This means that adequate observations and advanced computing resources must be available to adequately evaluate models and their potential utility for the public policy process. Consequently, there must be a greater commitment to advanced computing resources, as well as human resources, by the USGCRP to ensure that global modeling is achieved at spatial and temporal scales appropriate to the needs of the policy community and the private sector."

The Pathways Report represents a comprehensive look at the entire USGCRP. Several additional studies have addressed specific aspects of the program, and are discussed below.

Long-term Climate Observations

The NRC's 1999 Observing Systems Report warned of degradation of U.S. capabilities. Briefly, over the past several years, many in the national and international climate science community have pointed out serious and growing problems in our existing observation system, and, in particular, a need for additional attention to preserving and enhancing surface-based observational capabilities:

"The 1997 Conference on the World Climate Research Programme to the Third Conference of the Parties of the United Nations Framework Convention on Climate Change concluded that the global capacity to observe the Earth's climate system is inadequate and is deteriorating worldwide and that 'Without action to reverse this decline and develop the Global Climate Observation System, the ability to characterize climate change and variations over the next 25 years will be even less than during the past quarter century.' "

The report contained the following major finding and recommendation:

"FINDING: There has been a lack of progress by the federal agencies responsible for climate observing systems, individually and collectively, toward developing and maintaining a credible integrated climate observing system, consequently limiting the ability to document adequately climate change.

RECOMMENDATION: These agencies should work through the USGCRP process and at higher government levels to:

• stabilize the existing observational capability;

• identify critical variables that are inadequately measured;

• build climate observing requirements into the operational pro-grams as a high priority;

• revamp existing climate programs and some climate-critical parts of operational observing programs through the implementation of the ten principles of climate monitoring; and

• establish a funded activity for the development, implementation, and operation of climate-specific observational programs."

The panel also provided ten climate monitoring principles that should be applied to climate monitoring systems. These principles would ensure that the observations taken will be useful over the long term for studying climate processes and analyzing climate trends.

The panel made the following observation with regard to the governmental structure of the climate observing system:

"Today, no one agency has claimed a primary mission of long term, homogeneous climate observations. The evidence leads to the conclusion that this is an ancillary activity for all agencies involved in observations. Moreover, the USGCRP has neither the charter nor the ability to compel agencies to support programs they have failed to embrace. The consequence of these factors is that the institutional environment for developing and maintaining a credible, integrated climate observing system does not exist. This panel was not given the mandate for advising the USGCRP on how it should address this fundamental problem. Scientists can assist in evaluating the merits of proposed alternative solutions, but there are many non-scientific aspects of an institutional nature that will determine the choice of an ultimate solution. However, the panel believes the USGCRP, or its parent, CENR, should consider developing and adopting a strategic plan containing alternative options that would be responsive to resolving this problem. It could incorporate the involvement of administrators at appropriately high levels, including OSTP and OMB, to adopt or, if required, to seek Congressional approval for changes in agency objectives and programs."

Climate Modeling

The Pathways Report had a specific recommendation for improved climate modeling. The Climate Research Committee examined the issue in greater detail and reinforced the findings and recommendations of the Pathways Report. The Executive Summary of the Modeling Report states in part:

"The U.S. climate modeling research community is a world leader in intermediate and smaller climate modeling efforts—research that has been instrumental in improving the understanding of specific components of the climate system. Somewhat in contrast, the United States has been less prominent in producing high-end climate modeling results, which have been featured in recent international assessments of the impacts of climate change. The fact that U.S. contributions of these state-of-the-art results have been relatively sparse has prompted a number of prominent climate researchers to question the current organization and support of climate modeling research in the United States, and has led ultimately to this report."

"In this evaluation of U.S. climate modeling efforts, the Climate Research Committee (CRC) was asked … to address three key questions:

· "Regarding the first question—the CRC has reached the conclusion that, although individual federal agencies may have established well-defined priorities for climate modeling research, there is no integrated national strategy designed to encourage climate modeling that specifically addresses, for example, the objectives of the USGCRP, the needs for comprehensive contributions to the IPCC science base, and the priorities developed by the CRC in its chapter in the Board on Atmospheric Sciences and Climate's report, Atmospheric Sciences Entering the Twenty-First Century. We suggest that the science-driven climate modeling agenda, which has been largely shaped by individual investigators, has been reasonably effective in advancing the frontiers of science, but has not been adequately responsive to the immediate needs of the broader community (e.g., the "impacts" and "policy" communities)."

· "With respect to the second question—we find that, compared with intermediate and smaller modeling efforts, insufficient human and computational resources are being devoted to high-end, computer-intensive, comprehensive modeling, perhaps in part because of the absence of a nationally coordinated modeling strategy. Consequently, in contrast to some of the foreign modeling centers, U.S. modeling centers have found it difficult to perform coupled atmosphere–ocean climate change scenario simulations at the spatial resolutions relevant to certain national policy decisions (e.g., finer than 500 km x 800 km). The recognized strengths of U.S. intermediate modeling capabilities (see, e.g., the sizable contributions from the U.S. coarse-resolution climate modeling efforts in the IPCC reports) have not been effectively harnessed in the development of high-end, U.S.-based models. For instance, leading Earth system modeling efforts in the United States suffer from a computationally limited ability to test and run models in a timely fashion. The ability of the climate community to acquire state-of-the-art mainframes is severely hampered by a Department of Commerce "antidumping order" prescribing a financial penalty in excess of 400 percent on the purchase price of the world’s most powerful commercial supercomputers, which are Japanese in origin. The climate community has not been provided with the financial or computational resources to overcome this barrier and has, therefore, been unable to fully capitalize on the scientific potential within the United States. Not only is insufficient access to powerful computers hampering scientific progress in understanding fundamental climate processes, it is also limiting the ability to perform simulations of direct relevance to policy decisions related to human influences on climate. However, at least as important as the insufficiency of computing resources are the lack of national coordination and insufficient funding of human resources."

· "Regarding the third question—the CRC finds that:

"In order to avoid the aforementioned problem regarding priority setting, the USGCRP could assume increased responsibility for identifying, from an interagency perspective, any gaps or imbalances in the research priorities established by the individual agencies. At present, however, this is made difficult because some agencies have excluded from their USGCRP budgets the computational and human resources to support comprehensive, coupled atmosphere-ocean climate modeling efforts on a par with those in several foreign countries. Although an entirely top-down management approach for climate modeling is viewed as undesirable, national economic and security interests nevertheless require a more comprehensive national strategy for setting priorities, and improving and applying climate models. An effective national approach to climate modeling should ensure that available resources are allocated appropriately according to agreed upon science research and societal priorities and are efficiently utilized by the modeling community. We acknowledge that justification for and design of such a strategy would require a more complete evaluation of the current status of climate modeling in the United States than was possible in developing this report. Development of such a strategy should take place with full involvement of climate modelers within academia and the national climate research centers, along with users of climate modeling results and agency program managers."

"The CRC finds that the United States lags behind other countries in its ability to model long-term climate change. Those deficiencies limit the ability of the United States:

1. to predict future climate states and thus:
a) assess the national and international value and impact of climate change;
b) formulate policies that will be consistent with national objectives and be compatible with global commitments;
2. to most effectively advance understanding of the underlying scientific issues pertaining to climate variability and change."

"Although collaboration and free and open information and data exchange with foreign modeling centers are critical, it is inappropriate for the United States to rely heavily upon foreign centers to provide high-end modeling capabilities. There are a number of reasons for this, including the following:

Reconciling Temperature Observations.

The Reconciling Temperature Report is an example of an NRC report that tackles a particularly difficult or controversial issue in an attempt to illuminate the issue as much as possible. There had been an ongoing disagreement among various groups as to the nature of the change in the Earth's temperature. The question of surface measurements as contrasted to satellite measurements was the crux of the debate. The NRC convened a panel of experts in surface, weather balloon, and satellite measurements to address the issues and attempt to understand what the various data sources were telling us about the global temperature change. The Executive Summary of the resulting study states:

"The global-mean temperature at the earth’s surface is estimated to have risen by 0.25 to 0.4 ºC during the past 20 years. On the other hand, satellite measurements of radiances indicate that the temperature of the lower to mid-troposphere (the atmospheric layer extending from the earth’s surface up to about 8 km) has exhibited a smaller rise of approximately 0.0 to 0.2 ºC during this period. Estimates of the temperature trends of the same atmospheric layer based on balloon-borne observations (i.e., radiosondes) tend to agree with those inferred from the satellite observations. The panel was asked to assess whether these apparently conflicting surface and upper air temperature trends lie within the range of uncertainty inherent in the measurements and, if they are judged to lie outside that range, to identify the most probable reason(s) for the differences."

"To address these questions the panel had to consider:

• the factors that contribute to uncertainties in the trends inferred from three categories of instrumental measurements—Microwave Sounding Units (MSU) carried aboard National Oceanic and Atmospheric Administration (NOAA) satellites, radiosondes, and surface observations;

• the technical issues involved in making comparisons between global-mean temperature trends derived from measurements with different physical characteristics, different spatial and temporal sampling characteristics, and different error characteristics;

• the impact of the recent corrections to the algorithms for processing measurements derived from the MSU to account for satellite drifting and changes in instrument response;

• the contribution of natural climate variability to decade-to-decade climate changes, including changes in the atmosphere's vertical structure associated with natural variability;

• the changes in the atmosphere's vertical structure associated with human-induced climate changes; and

• the results of recent climate model simulations of temperature trends that take into account both natural variability and human-induced forcing."

"In the opinion of the panel, the warming trend in global-mean surface temperature observations during the past 20 years is undoubtedly real and is substantially greater than the average rate of warming during the twentieth century. The disparity between surface and upper air trends in no way invalidates the conclusion that surface temperature has been rising. The recent corrections in the MSU processing algorithms (referred to above) bring the global temperature trend derived from the satellite data into slightly closer alignment with surface temperature trends, but a substantial disparity remains. The various kinds of evidence examined by the panel suggest that the troposphere actually may have warmed much less rapidly than the surface from 1979 into the late 1990s, due both to natural causes (e.g., the sequence of volcanic eruptions that occurred within this particular 20-year period) and human activities (e.g., the cooling of the upper part of the troposphere resulting from ozone depletion in the stratosphere). Regardless of whether the disparity is real, the panel cautions that temperature trends based on data for such short periods of record, with arbitrary start and end points, are not necessarily indicative of the long-term behavior of the climate system."

"Reducing uncertainties in the evaluation of the trends will require: (1) implementing an improved climate monitoring system designed to ensure the continuity and quality of critically needed measurements of temperature, other climatic variables, and concentrations of aerosols and trace gases; and (2) making raw and processed atmospheric measurements accessible in a form that enables a number of different groups to replicate and experiment with the processing of the more widely disseminated data sets such as the MSU tropospheric temperature record. A number of possible research strategies for improving the understanding of uncertainties inherent in the various measurement systems and the relationship between surface and upper air temperature trends are proposed in the report."

In this report, the need for better observations and models was also noted.


This is but a brief description of some of the many NRC activities concerning the USGCRP. The USGCRP is vital to improving our understanding of how the Earth system is changing, and of the human role in such change. We have seen some of the NRC recommendations embraced by the USGCRP, but I believe it is fair to say that the present agency activities in adopting the NRC recommendations are yet to be evaluated. The adoption of the NRC recommendations for more focused research programs, better observations, and better modeling capability will enable the community to learn much more about the potential consequences of change for ecosystems and for human society.

Thank you, Mr. Chairman. I would be happy now to answer your questions.