TESTIMONY OF
D. JAMES BAKER
UNDER SECRETARY OF COMMERCE FOR OCEANS AND ATMOSPHERE
AND
ADMINSTRATOR, NATIONAL OCEANIC AND ATMOSPHERIC ADMINSTRATION
BEFORE THE
SUBCOMMITTEE ON ENERGY AND ENVIRONMENT
OF THE
COMMITTEE ON SCIENCE
UNITED STATES HOUSE OF REPRESENTATIVES

March 9, 2000

Introduction

Thank you for this opportunity to discuss with you the Administration’s FY2001 budget proposal for the US Global Change Research program (USGCRP). I know the Members of this Subcommittee, and the Science Committee as a whole, have been strong supporters of this research program, which is one of our nation’s most important scientific efforts. The USGCRP began as a Presidential Initiative in 1989, and was codified by the Global Change Research Act of 1990. Every Administration and Congress has strongly backed the program since its inception. While we may have some differences of opinion on precisely how and where to invest our taxpayers’ funds, we share a bipartisan understanding that the future prosperity of this country depends on strong federal support for all areas of scientific inquiry.

The President and the Vice President consider global change research to be one of the foundations of a sustainable future. The Administration looks forward to working with the Congress to carry on this bipartisan tradition of support for sound science on this subject.

The Budget in Brief

The overall FY 2001 USGCRP Budget Request is approximately $1.74 billion dollars, about 2 percent higher than last year’s enacted level. Within the total, support for scientific research is up about $53 million (7%), including a $31 million increase for carbon cycle studies at USDA as part of the carbon cycle research initiative begun last year. Surface-based observations at NOAA are receiving a substantial increase ($26 million, or about 39%) that will help provide new information on changing patterns of temperature and rainfall in the US. The total increase for surface-based observations and science together is about $79 million, or 10%. The space-based observation component of the budget is reduced by about $40 million, to a total of $897 million. This decrease is mainly a consequence of decreases in NASA development costs as the first Earth Observing System (EOS) satellites (e.g., Terra and Aqua) are completed and launched.

The fact that the increase in science funding more than offsets the decrease in funding for space-based observations is important. Increasing the proportion of program funding for science has been one of the most consistent recommendations from the National Research Council and various agency advisory committees over the last few years. The National Research Council (NRC) report, Global Environmental Change: Research Pathways for the Next Decade, noted that 65 percent of the total USGCRP were devoted to space-based observations and data systems in the 1996 budget proposal. In this year’s budget proposal, the equivalent number is about 52 percent. Important highlights of the FY2001 budget proposal include:

Improved Climate Observations. The FY 2001 budget provides $26 million to enhance NOAA surface-based observations, including creation of a climate reference network to provide, for the first time, simultaneous, automated, and ideally located measurements of changing temperatures, precipitation and soil moisture. Measurements of atmospheric trace gases, aerosols, ocean temperatures, and ocean currents will also be expanded.

The Global Water Cycle. The FY 2001 budget provides $308 million (an increase of $35 million, or about 13%) for research on changes that appear to be occurring in the Earth’s water cycle -- one of the primary determinants of the Earth’s climate. The launch of NASA’s EOS Aqua spacecraft in December 2000 will support this research by providing new global measurements of humidity, cloud properties, precipitation, snow, and sea ice.

Ecosystem Changes. The FY 2001 budget provides $224 million for research on the potential impacts of climate change and other stresses on forests, coastal areas, croplands, and other ecosystems (an increase of $19 million, or 9%). New studies will help identify "thresholds" for significant changes in ecosystems.

Carbon Cycle Initiative. The FY 2001 budget request continues strong support for the multi-agency carbon cycle science initiative begun in FY 2000, providing $229 million (an increase of $23 million or 11%) to study how carbon cycles between the atmosphere, the oceans, and land, and the role of farms, forests, and other natural or managed lands in capturing carbon. Key agencies include USDA, DOE, NASA, NSF, DOI, and the Smithsonian Institution.

A Record of Accomplishment

Global change is an extremely complex scientific topic. Explaining how the Earth system functions, how it is changing, and how it is likely to change under increasing human interventions in the future requires a coordinated research effort that cuts across many different scientific disciplines. The success of the USGCRP in marshalling such an effort, combined with strong support from Congress and the Administration for global change research, has led to a remarkable increase in our understanding.

Over the past decade, the U.S. Global Change Research Program (USGCRP) has achieved an impressive number of scientific advances:

Scientists have conducted an intensive study of ozone depletion, including monitoring the spatial extent and temporal behavior of the Antarctic ozone hole. Observations have demonstrated an ongoing and statistically significant decline in ozone amounts over most of the Earth, much of which is attributable to changes in atmospheric chemistry associated with human activities.

Our understanding of the El Nino-Southern Oscillation (ENSO) has been greatly improved. We now know that this phenomenon, as well as its effect on climate around the world, has a degree of predictability.

Observations and analyses have demonstrated that emissions of carbon dioxide and other trace effluents of human society are changing the composition of the atmosphere. It is projected that over the next century the abundance of some greenhouse gases will increase to levels not seen in millions of years.

There is now a near unanimous consensus that the surface of the Earth is indeed warming. There is also general agreement that emission of greenhouse gases by society is responsible for at least part of this temperature increase.

Substantial improvements in climate models have been made over the last decade. Refining spatial resolution, improving representations of land surface processes, and taking the initial steps to include the climatic effects of aerosols and ozone depletion have resulted in model simulations that more closely match the observed temperature record over the last century. Along with the ability to carry out ensembles of simulations, these improvements are lending greater credibility to projections of change in climate over the next century.

The ongoing observations from the Landsat satellite series (recently extended by the successful launch of Landsat-7) have provided an accurate record of changes in land cover and land use, permitting quantitative assessments of deforestation rates in tropical areas.

Over the next several years, in addition to continuing to improve our understanding of the Earth’s environment and how it is changing, we expect the program will greatly advance our knowledge about the implications of such change for society through the conduct of periodic assessments as called for under the Global Change Research Act.

Organization of the U.S. Global Change Research Program

The agencies who participate in the USGCRP are USDA, DOC/NOAA, DOE, HHS, DOI, DOT, EPA, NASA, NSF, and the Smithsonian Institution.

During the last year, the USGCRP has been refining its research priorities as it engages in the process of developing a new, long-term research strategy for the next decade. The NRC Pathways report, which the USGCRP commissioned, has influenced the definition of the near-term research challenges and is also serving as important input for the long-term strategy. The USGCRP is organized as a series of closely linked program elements that are directly responsive to the scientific challenges described in the Pathways report:

Understanding the Earth's Climate System, with a focus on improving our understanding of the climate system as a whole, rather than its individual components, and thus improving our ability to predict climate change and variability.

Biology and Biogeochemistry of Ecosystems, with a focus on improving understanding of the relationship between a changing biosphere and a changing climate and the impacts of global change on managed and natural ecosystems.

Composition and Chemistry of the Atmosphere, with a focus on improving our understanding of the impacts of natural and human processes on the chemical composition of the atmosphere at global and regional scales, and determining the effect of such changes on air quality and human health.

Paleoenvironment and Paleoclimate, with a focus on providing a quantitative understanding of the patterns of natural environmental variability, on timescales from centuries to millennia, upon which the effects of human activities on the planet's biosphere, geosphere, and atmosphere are superimposed.

Human Dimensions of Global Change, with a focus on explaining how humans affect the Earth system and are affected by it, and on investigating the potential response strategies for global change.

The Global Water Cycle, with a focus on improving our understanding of how water moves through the land, atmosphere, and ocean, and how global change may increase or decrease regional water availability.

Carbon Cycle Science, with a focus on improving our understanding of how carbon moves through the Earth’s terrestrial ecosystems, soils, ocean, and atmosphere.

Before turning to a more detailed description of recent accomplishments and FY2001 plans in most of these areas, I would like to highlight a few items of special priority.

The Carbon Cycle Initiative

We are continuing to increase our emphasis on Carbon Cycle Science in FY2001. We need to improve our understanding of how carbon moves through the Earth’s atmosphere, land, and water, the sources and sinks of carbon on continental and regional scales, and how such sinks may change or be enhanced. This was among the strongest recommendations of the Pathways report. The USGCRP, through interactions with the scientific community and active program managers, established a Carbon Cycle Science Initiative in the FY 2000 budget. The Departments of Agriculture, Energy, Interior, the National Aeronautics and Space Administration, the National Science Foundation, the Department of Commerce’s National Oceanic and Atmospheric Administration, and the Smithsonian Institution will all play important roles in this effort, guided by a science plan that has been drafted with participation by many of the leading scientists in this field.

The Carbon Cycle Science Initiative will employ a wide variety of research activities in a comprehensive examination of the carbon cycle as an integrated system, with an initial emphasis on North America. Comparison of North America to other regions will also be important for understanding the relative importance of our region in the global context. Atmospheric and oceanographic sampling field campaigns over the continent and adjacent ocean basins will be combined with atmospheric transport models to develop more robust estimates of the continental and subcontinental-scale magnitude and location of the North American carbon sink. Local-scale experiments conducted in various regions will begin to identify the mechanisms involved in the operation of carbon sinks on land, the quantities of carbon assimilated by ecosystems, and how quantities might change or be enhanced in the future.

The initiative will also include evaluation of information from past and current land-use changes, both from remotely sensed and historical records, to assess how human activity has affected carbon storage on land. Agency and academic researchers will study potential management strategies for maximizing carbon storage, including evaluation of the variability, sustainability, lifetime, and related uncertainties of different managed sequestration approaches. Finally, enhanced long-term monitoring of the atmosphere, ocean, forests, agricultural lands, and range lands, using improved inventory techniques and new remote sensing, will be used to determine long-term changes in carbon stocks. Integration of new observations and understanding of carbon cycle processes in regional and global carbon system models will enable us to more accurately project future atmospheric concentrations of carbon dioxide and other greenhouse gases.

The recent impressive scientific progress in carbon cycle research shows that this area is ready for investment and progress:

Scientists have extended the climate and trace-gas record back to 400,000 years before the present through studies of Antarctic ice cores. This record shows that the increase in CO2 in the atmosphere over the last century has resulted in higher atmospheric concentrations than previously seen during this entire period of time.

Investigators have pioneered the use of high-precision measurements of the O2/N2 ratio in air to study the biogeochemical cycles of carbon and oxygen. The combination of atmospheric O2/N2 and CO2 provides a powerful tool to study the fate of fossil fuel CO2 because it allows discrimination between uptake via inorganic dissolution in the oceans (which does not release oxygen) and photosynthesis (which does release oxygen). The record to date has revealed significant interannual variability in the magnitude of the terrestrial biospheric sink for CO2. The anomalous absence of net sequestration of atmospheric carbon by the terrestrial biosphere in 1998 may be due to the 1997-1998 El Niño event. The ability to monitor these fluxes in real time will be a critical asset in developing the capability for managing a national or global carbon emission strategy.

Scientists measured air-sea CO2 flux directly for the first time using meteorological techniques on-board ship. This result paves the way for progress in understanding the processes controlling uptake of carbon by the ocean.

Scientists have shown that, by mixing colder waters upward, hurricanes significantly increase the CO2 transport from ocean to atmosphere. Increasing CO2 concentration in the atmosphere is expected to affect climate, while climate change may also have a feedback effect on the CO2 exchange between atmosphere and ocean.

The highest priority for FY2001 will continue to be on understanding and quantifying North American carbon sources and sinks, and on filling critical gaps in our understanding of the causes of carbon sinks on land as well as processes controlling the uptake and storage of carbon in the ocean. Research advances on these questions will provide information needed as a basis for sound policymaking, as well as valuable information about potential management strategies to land and forest managers in both the public and private sectors.

Long-term Climate Observations

The NRC’s 1999 Adequacy of Climate Observing Systems report, which warned of degradation of U.S. capabilities, has had a significant effect on the USGCRP. 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 FY2001 budget proposes an augmentation of $28 million to the NOAA budget that is dedicated to enhancing the long-term surface-based observations that are needed for climate change research. This includes funding for the creation a new Climate Reference Network, which will enable creation of an in situ network driven strictly by long-term climate observing requirements. Automated stations in ideal sites will make very accurate measurements of precipitation, temperature, and soil moisture. The FY2001 budget contains funds for the establishment of 100 stations. There is also FY2001 funding for upgrade and expansion of the long-term measurements of atmospheric trace gases and aerosols at the Alaska, Hawaii, Samoa, and Antarctica observatories and also for enhanced observations of the oceans. Finally, we have included support for improving the availability and distribution of these climate data and forecasts to the scientific community and general public.

These new resources will be managed within the context of the USGCRP, and they will help us build on the progress of the last year, which has seen a series of important enhancements to our nation’s observational programs, both inside and outside the traditional USGCRP. We are improving our ocean observing capabilities by deploying additional buoys in the Atlantic and northern Pacific oceans and modernizing the cooperative observer network that supplies temperature and precipitation data that are useful for both climate and weather research. Most significantly, we have seen the successful deployment of a number of new NASA satellites, including Landsat-7, QuickSCAT, ACRIMSAT, and EOS TERRA. It is no exaggeration to say that we have begun a new era in Earth observations. These new satellites will provide unprecedented amounts of high quality data on land cover, clouds, vegetation, surface winds, solar irradiance, ocean temperatures, and other variables to USGCRP researchers and other users. These data are critical to understanding how the Earth system is changing, and I am confident that we will be able to look back in ten years and see that their availability led to major scientific advances. The successful development and deployment of these missions is a credit to NASA and its international and interagency partners.

An important aspect of getting the most out of these improvements in technology over the long term will be the development of a closer relationship between the research and operational communities in both space-based and surface-based observing programs and scientific research programs. We are making progress in this area as well, with deeper involvement by the USGCRP research community in the design and development of the next generation of operational systems, such as the National Polar-orbiting Operational Environmental Satellite System (NPOESS).

The National Assessment of the Potential Consequences of Climate Variability and Change

Many greenhouse gases have very long atmospheric lifetimes and their effects are also long-lived. The Earth has warmed by about 1 degree F over the last 100 years. The long-term nature of the atmosphere’s response to greenhouse gases that have already been emitted commits us to a degree or more of additional warming. Although it is clear that reducing emissions will slow the increase in atmospheric concentrations and reduce the amount and rate of climate change in the future, some further change is inevitable because of the emissions that have already occurred.

The National Assessment effort now underway in the USGCRP is examining the degree to which particular regions and sectors of the U.S. are vulnerable to climate change, the potential ecological and socioeconomic impacts of climate change, and how we can best adapt and prepare for the coming changes. The USGCRP has sponsored about twenty regional workshops over the last several years to identify regional issues of concern, and has sponsored a series of regional assessment efforts under the leadership of regional academic institutions. Teams led by academic institutions are also drafting a series of sectoral assessment reports. A team of authors, that includes academic, industrial, non-governmental organization, and government scientists -- chartered under the Federal Advisory Committee Act – is drafting the National Assessment Synthesis Report. We expect the report to be completed in a few months. This type of assessment is required under the U.S. Global Change Research Act.

Climate Modeling

With respect to climate modeling, we are continuing along the course set last year by coordinating USGCRP activities with the Administration’s Information Technology (IT) for the Twenty-first Century Initiative. We have implemented some important upgrades at U.S. climate modeling centers, including the National Center for Atmospheric Research and the NOAA Geophysical Fluid Dynamics Laboratory, and are making good progress in the development of a common modeling infrastructure that will make it easier to share advances among different groups. We are also investing in the development of new models that will be better able to use the dramatic increases in supercomputing power that are anticipated through the IT initiative. The development and operation of high-end General Circulation Models is an extremely computer-intensive application. The climate modeling community is clearly at the forefront of the research disciplines that require and are ready to make use of new computing capabilities.

Let me turn now to description of the core areas of the USGCRP research program, which includes a brief summary of current research efforts, recent accomplishments, and 2001 plans. The USGCRP will present specific performance metrics in the FY2001 version of "Our Changing Planet," which we plan to deliver to Congress in the near future.

Understanding the Earth's Climate System

The budget proposes $487 million for programs related to understanding the Earth’s climate system. Climate is a naturally varying and dynamic system with important implications for the social and economic well being of our societies. Understanding and predicting climate changes across multiple time scales (ranging from seasonal to interannual, to decadal and longer) offers valuable information for decision making in those sectors sensitive to rainfall and temperature fluctuations, including agriculture, water management, energy, transportation, and human health. Improving our understanding of climate change, and determining how much of the observed changes in the climate are attributable to human activities, and how much to natural variability, requires that we improve our understanding of both natural variability and human effects. Such improvement depends on a balance of observations, studies of underlying Earth system processes (such as the El Nino), and predictive modeling.

Recent Research Accomplishments:

We continue to develop a more refined understanding of the temperature changes over the last century. There has been a significant increase in the rate of warming in the last twenty years. The 11 warmest years in the 120-140 year instrumental record of global average temperatures have all occurred since 1983. The three warmest years on record were 1998, 1997, and 1995, in that order. 1999 was the fifth warmest year on record; despite the fact that there was a very large El Nino event that was expected to result in cooler temperatures.

Observations and models have demonstrated a link between decadal variations in the production of Labrador Sea water and large-scale surface temperature anomalies in the tropical Atlantic. This suggests there is a link between climate variability at high and low latitudes, via a mechanism that affects sea-surface-temperature variability in the tropical Atlantic that is quite different from the El Niño-Southern Oscillation (ENSO) dynamics that dominate the tropical Pacific. It also suggests that the deep ocean may influence climate variability on decadal time scales.

Observations show that the thickness of Arctic sea-ice has declined by about 40 percent compared to 20-40 years ago, and that the areal extent of the ice has also been reduced. This thinning cannot at this time be directly attributed to climate change, but it is a major "climate signal" that must be taken account of in explanations of variability or change. Model simulations of arctic sea ice extent indicate that the observed declines in areal extent are unlikely to have occurred due to natural variability, suggesting that at least part of the decline is attributable to human activity.

FY2001 Plans:

The USGCRP will study longer-term (multi-decadal) natural climate cycles, including the Pacific-Decadal Oscillation, the North Atlantic Oscillation, and the Arctic Oscillation. Our hope is to improve our understanding of the impacts of these oscillations on storms, floods, and other extreme weather events, and to improve our understanding of the relationships of such cycles and long-term human-induced climate change. The USGCRP Climate Variability (CLIVAR) Atlantic Program will continue its research thrust to understand and predict seasonal to decadal climate variability in the tropical Atlantic Ocean in the context of other natural modes of climate variability. An enhanced understanding of impacts of climate variability offers valuable information for planners and decision-makers, as evidenced by the 1997-1998 El Nino event. The USGCRP will also improve the representation of the Earth’s climate system in models. Specifically, improvements in small-scale processes, finer spatial resolution, and better representation of land-surface energy and water exchanges are top priorities. The USGCRP will complete a 500-year simulation of the large-scale features of the global climate system, to be conducted with the new version of the community Climate System Model, CSM2. The model data will be used to evaluate the ability of CSM2 to simulate natural climate variability on seasonal to centennial timescales.

Biology and Biogeochemistry of Ecosystems

The budget proposes $224 million in FY2001 for the study of changes in managed and unmanaged ecosystems. The biosphere consists of diverse ecosystems that vary widely in complexity and productivity, in the extent to which they are managed, and in their economic value to society. Ecosystems directly provide forage, timber, fish, food, and fiber, as well as other services such as water cycling, climate regulation, recreational opportunities, and wildlife habitat. Ecosystems both respond to and contribute to global change. Management of ecosystems and natural resources will be an important aspect of society's response to global change. Ecosystems have the capacity to respond to stress; however, when that capacity is exceeded, natural resources and services are altered and begin to decline. Our ability to achieve a sustainable future depends on the protection of public lands and other lands, the sustainable use of terrestrial and aquatic renewable resources, and more efficient use on non-renewable resources. Better scientific understanding of the processes that regulate ecosystems and the capability to predict ecosystem changes and evaluate the potential consequences of management strategies will improve the ability to manage for sustainability.

Recent Research Accomplishments:

Research has documented significant changes in the growth and development of ponderosa and Jeffrey pine in response to ozone exposure and nitrogen deposition. Root biomass decreases with exposure to air pollution, raising important questions about predisposing trees to drought-induced mortality and related insect attacks. The interaction of ozone and nitrogen pollution has serious implications for the storage of carbon both in soils and above ground in ecosystems subject to air pollution.

New dynamic ecosystem modeling simulations indicate that climate change could lead to increased fire frequency over much of the western U.S. and, under the scenarios that project the greatest warming, over many of the eastern U.S. forests.

Scientists found that a widely used herbicide loses its effectiveness as CO2 levels increase. Research showed that, for a common weed (lambsquarters), the application of the recommend dose killed 100 percent of the weed at current ambient CO2 levels, but higher doses were required at double the ambient CO2 levels. This finding indicates that weed management strategies may require modification in the future as atmospheric composition changes.

Scientists demonstrated how an increasing CO2 concentration affects the growth of undesirable species such as mesquite in U.S. grazing lands. An elevated CO2 concentration reduces water loss by native grasses and increases soil moisture. These changes in soil moisture were associated with an 80 percent increase in mesquite seedling establishment and a 40 percent increase in seedling growth. These results suggest that changes in atmospheric composition may have a deleterious effect on rangeland species composition.

FY2001 Plans:
The USGCRP will complete studies that advance our understanding of the relationships among land cover, land use, biodiversity, climate, and weather, including quantifying rates of land use change and its effects on atmospheric chemistry and biodiversity in tropical areas such as Central Africa and SE Asia. In addition, Research designed to test ecosystem resilience to single and multiple stresses will be undertaken. The program will also develop criteria and indicators of ecosystem sensitivity and sustainability to link landscape scale changes and disturbance regimes with ecosystem carrying capacity. The USGCRP will also develop advanced ecological and biogeochemical cycling models that blend processes occurring across time spans of days to centuries and realistically portray the effects of disturbance and land use history. Finally, the USGCRP will evaluate the initial results of multiple long-term field experiments designed to improve understanding of the above and below ground responses of intact terrestrial ecosystems to changes in atmospheric composition and climate variables.

Composition and Chemistry of the Atmosphere

The Budget proposes $368 million for programs studying the composition and chemistry of the atmosphere. Changes in the global atmosphere can have important implications for life on Earth, including such factors as the exposure to biologically damaging ultraviolet (UV) radiation, the abundance of greenhouse gases and aerosols (which in turn affect climate), and regional air pollution. Human activity that can affect atmospheric composition includes the use of chlorofluorocarbons and other halogenated hydrocarbons, fossil fuel combustion and the associated release of air pollutants, and changes in agricultural practices that affect the concentration of gases such as nitrous oxide and methane, as well as that of smoke. As a result, this research is a central component of our effort to understand global change.
Recent Research Accomplishments:

The Indian Ocean Experiment (INDOEX) is a cooperative program involving scientists from the United States, Europe, India, and the Maldives. The field phase of INDOEX was successfully conducted over the Indian Ocean during winter-spring 1999. INDOEX scientists have, for the first time, documented the chemical and physical properties of natural and human-produced atmospheric aerosols and trace gases over the Indian Ocean. They are now using these observations to study and model the complex interactions between atmospheric aerosols, gas-phase chemicals, clouds, and radiative forcing of climate.

Recent measurements of chlorine in the stratosphere have show that total chlorine in that region is declining. This is a direct result of the international effort to ban chlorofluorocarbons (CFCs). As the use of these chemicals is phased out, the ozone layer is expected to begin recovering, a process that will take about 50 years.

FY2001 Plans:

The USGCRP will significantly improve the measurements of atmospheric trace gases and aerosols. The operations of the Global Atmospheric Baseline Observatories in Barrow Alaska, Mauna Loa, Hawaii, American Samoa, and at the South Pole will be upgraded and expanded, and routine aircraft flask profile measurements of trace gases and aerosols will be expended to cover the continental U.S. and Pacific Basin. In addition, the USGCRP will continue studying the chemistry of stratospheric ozone and initiate new studies of tropospheric ozone and the impact of ozone and aerosols on radiative forcing in the east Asia/western Pacific region. The USGCRP will also extend the data record for atmospheric ozone using the QuikTOMS spacecraft launched in FY2000 and the SAGE III instrument, planned for launch in late FY2000. Finally, the USGCRP interagency ground-based UV network will continue to provide long-term, highly calibrated observations of surface UV flux and make data available to users in the physical science, ecology, and human health communities.
Paleoenvironment and Paleoclimate

The budget proposes $27 million in FY2001 for the study of the Earth’s past environment. The Earth’s climate and environmental history has been long, amazingly complex, and marked by enormous changes. Paleoenvironmental records are derived from a wide variety of natural archives, such as lake and ocean sediments, tree rings, wind-blown deposits, coral, and ice cores, as well as historical documents. In most locations, instrumental records might provide 100 years of climate data, whereas an ice core might provide an annual climate record of 10,000 to 30,000 years. Reconstructing the historical climate record offers an enhanced understanding of the mechanisms controlling the Earth's climate system and, together with insight obtained from numerical modeling exercises, provides a foundation for anticipating how the planet might respond to future environmental perturbations.
Recent Research Accomplishments:

"Proxy" temperature records embodied in glaciers and ice sheets, lake sediments, corals, tree rings, and the like, show that the last 10 years have been the warmest decade (and 1998 appears to have been the warmest year) on Earth in 1,000 years. Analysis of temperature measurements from boreholes indicates that the surface temperature of the late 20th century is without precedent in the last 500 years, with 80 percent of the warming over the last 500 years occurring since 1800, and 50 percent since 1900.

Millennial variations of sea-surface temperature off California have been shown to have occurred within a few decades, and correlate with atmospheric temperature fluctuations over Greenland during the last glacial interval. Similarly, ocean floor cores from the Santa Barbara Basin have given an unparalleled oceanic climatic record that shows rapid, abrupt warmings and coolings (with 5( C sea-surface warmings in a few decades) that are synchronous with similar climatic responses recorded in the Greenland ice sheet. These results suggest that atmospheric warming and cooling events serve as an amplifying agent in promoting global ocean temperature change, and that climate changes have global-scale correlations and can occur very quickly.

FY2001 Plans:

The USGCRP will implement a program to obtain detailed paleoenvironmental information using a newly acquired drilling system for obtaining sediment cores from beneath large lakes. These sediments are the primary source of long-term paleoenvironmental records from continental areas and the acquisition and study of such sediments has been the object of years of planning and coordination work. The USGCRP will also explore the climatic linkages between oceanic and continental processes. Records of past conditions from coral and marine sediment will be combined with continental records from lake sediments and tree rings to establish the history of climate system changes along the Pacific coast of North America. Finally, the USGCRP will form a working group that will bring together members of paleoclimate and climate dynamics research communities to address the nation’s top climate research priorities and expand and improve the use of paleoclimate data in modern climate applications.

Global Water Cycle

The Budget proposes $308 million in FY2001 to study the global water cycle. The cycle of water through the land, atmosphere, and ocean is intimately tied to the Earth’s climate through processes including latent heat exchange and the radiative effects of water in its vapor, liquid, and solid phases. The water cycle is emerging as a top research priority because changes appear to be occurring already. Long-distance atmospheric transport of water, along with evaporation and precipitation, are the principal inputs in hydrologic process and water-resource models. The primary goal of this research is a greater understanding of the seasonal, annual, and interannual mean state and variability of water and energy cycles at continental-to-global scales, and thus a greater understanding of the interactions among the terrestrial, atmospheric, and oceanic hydrosphere in the Earth’s climate system.
Recent Research Accomplishments:

Continued successful operation of the Tropical Rainfall Measuring Mission (TRMM) satellite resulted in another year of instantaneous measurements of rainfall rates and monthly accumulations in the global tropics, where two-thirds of global precipitation occurs. The data are key to understanding the Earth's hydrological cycle. Past uncertainties in global tropical rainfall estimates are about 50%; data from TRMM will reduce this uncertainty to 10%. TRMM data are available to the general public through EOSDIS, the EOS Data and Information System.

EOS-Terra (previously called EOS-AM), the flagship of the Earth Observing System satellite series, was successfully launched in December 1999. The instruments on this satellite, including the Multi-angle Imaging SpectroRadiometer (MISR), the Clouds and the Earth's Radiant Energy System (CERES), the Moderate-resolution Imaging Spectroradiometer (MODIS), and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) will provide unique data on clouds, which will greatly advance our understanding of the hydrological cycle.

FY2001 Plans:

The USGCRP will, in collaboration with the science community, complete a comprehensive and detailed Water Cycle Science Plan that will define key research questions and set near-term and longer-term observational, modeling, and research priorities. TRMM operations will continue, and the USGCRP will begin a series of investigations of various elements of the global water cycle using data from the EOS-Aqua satellite, scheduled for launch in December 2000. EOS-Aqua will provide measurements of atmospheric temperature and water vapor profiles, radiation budget, clouds, precipitation, sea surface winds and temperature, among other variables. Finally, the USGCRP will continue to improve the representation of cloud processes and feedbacks in climate models through a variety of approaches including the use of cloud-resolving models.

Human Dimensions of Global Change

The budget proposes $93 million in FY2001 for the study of the human dimensions of global change. Scientific uncertainties about the role of human socioeconomic and institutional factors in global change are as significant as uncertainties about the physical, chemical, and biological aspects of the Earth system. Improving our scientific understanding of how humans cause changes in the Earth system, and how society, in turn, is affected by the interactions between natural and social processes, is an important priority for the USGCRP. Key questions include the following. What are the major human drivers of changes and how do they vary temporally, spatially, and across economic sectors and social groups? What are the human consequences of global environmental change? How might global change affect key life support systems (water, health, agriculture), economies, and political systems?

Recent Research Accomplishments:

Integrated assessment studies are increasing the understanding of the relationship between climate change and human responses. For example, research suggests that concerns about storms and the damage they cause have been far more important to coastal property owners than is potential damage from long-term sea-level rise associated with global climate change. Substantial damage from large, infrequent storms generally discourages rebuilding in vulnerable areas. In contrast, more common storms causing minor damage tend to lead homeowners to repair their property, although over the long run, the cumulative damage they suffer often exceeds the value of the property itself. More generally, scientists have found that people fear projected future changes in their environments, but that small events and slowly-changing environmental conditions rarely generate levels of concern that lead people to adopt new adaptation or mitigation strategies.

Researchers are studying how different land-ownership arrangements affect the management of different kinds of forest ecosystems in the U.S. and Latin America. New techniques have been developed to interpret remotely-sensed data, which are integrated with data from vegetation inventories, soil analyses, censuses and other sources of human population data, institutional analyses, and household-level socioeconomic surveys. Research finds that people adopt a far greater number and more complex set of rules to overcome obstacles to common-pool resource management than previously recognized, suggesting that polycentric, multi-level governance systems are more likely to achieve sustainable resource use than is reliance on single-level solutions, such as governmental control or privatization of all common-pool resources.

FY2001 Plans:

It is expected that the results of the first National Assessment of climate change will play a significant role in defining future research needs in this area. USGCRP agencies will implement regional assessment research projects on weather-related morbidity, the effects of global change on aquatic ecosystems, the consequences of global change on tropospheric ozone, and the impacts of climate variability. Additionally, the USGCRP will enhance its multi-disciplinary research on the complex processes through which individuals and organizations perceive, identify, explore alternatives, and respond to a range of short-term and long-term environmental hazards and risks. Finally, research on human health consequences of global change, including the effects of combined exposures to climatic and environmental factors and the development of climate models that are more location and time sensitive for human health impacts assessments will be undertaken.

Conclusion:

This brief description does not do full justice to the many activities taking place within the USGCRP, nor does it give a full picture of the many accomplishments that have occurred in the past year and the past decade. But it does show that the USGCRP is continuing a broad and successful program of research on global change that is improving our understanding of how the Earth system is changing, and of the human role in such change. As we look ahead to the next year, and the next decade, we can expect to develop a much fuller understanding of the processes of change. The sustained bipartisan support for global change research has not only enable steady scientific progress, but has also resulted in the development of a new generation of tools that offer the promise of more rapid progress in the years ahead. We will benefit from unprecedented amounts of data about the Earth, and these data will be of higher quality than ever before. We will develop more complex and accurate models that permit more realistic simulation of the Earth system. Most importantly, we can expect to learn much more about the potential consequences of change for ecosystems and for human society.

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