Decision-Support Resources Development & Related Research on Human Contributions and Responses
USGCRP Program Element

One of the main purposes of CCSP is to provide information for decisionmaking through the development of decision-support resources. Decision-support resources, systems, and activities are climate-related products or processes that directly inform or advise stakeholders to help them make decisions. These products or processes include analyses and assessments, interdisciplinary research, analytical methods (including scenarios and alternative analysis methodologies), model and data product development, forecasts, communication, and operational services. Decision-support resources and activities include research activities based in the natural sciences and activities related to human contributions and responses to climate variability and change, such as demography, economics, history, anthropology, political science, and sociology.

Decision Support Goal 1: Scientific Syntheses and Assessments

A primary activity within CCSP is the development of 21 synthesis and assessment products (SAPs) to support informed decisionmaking on climate variability and change by a broad group of stakeholders, including policymakers, resource managers, media, and the general public. The development of these SAPs stems from the Global Change Research Act (GCRA) of 1990 (P.L. 101-606, section 106), which directs the program to "produce information readily usable by policymakers attempting to formulate effective strategies for preventing, mitigating, and adapting to the effects of global change" and to undertake periodic science "assessments."

As of September 2007, the following synthesis and assessment products have been released:

1.1 Temperature Trends in the Lower Atmosphere: Steps for Understanding and Reconciling Differences

2.1 A. Scenarios of Greenhouse Gas Emissions and Atmospheric Concentrations and
B. Global-Change Scenarios: Their Development and Use.

Several other SAPs are expected soon. The accompanying box provides a brief description of the scope of each product. Up-to-date status on all SAPs can be found at the U.S. Climate Change Science Program.

CCSP supports research and tool development that focus on human behavior and socioeconomic trends. Assessments need to incorporate projections of social and economic change (e.g., population and technological change), as well as the effects of environmental change on communities and sectors (e.g., transportation, health, agriculture). Decision support also requires methods and tools to undertake comparative work across communities, regions, and sectors.

CCSP Goal 1: Improve knowledge of the Earth's past and present climate and environment, including its natural variability, and improve understanding of the causes of observed variability and changes. Synthesis and Assessment Product 1.1 Temperature Trends in the Lower Atmosphere: Steps for Understanding and Reconciling Differences Temperature change is a fundamental measure of climate change. This product, which was the first to be completed, addresses temperature changes from the surface through the lower stratosphere and understanding of the causes of these changes. It assesses progress made since the reports by the National Research Council (2000) and the Intergovernmental Panel on Climate Change (2001) and highlights differences between the individual temperature records determined by components of the existing observational and modeling systems and documents the potential causes of these differences. Synthesis and Assessment Product 1.2 Past Climate Variability and Change in the Arctic and at High Latitudes The Arctic and the high latitudes have warmed more rapidly than almost any other region on Earth over at least the last millennium. This warming has been accompanied by a decrease in sea ice cover and thickness and a decrease in ocean salinity. In addition, significant changes in the permafrost active layer are now being detected. The impacts on humans and ecosystems that are associated with these changes were reported in the Arctic Climate Impact Assessment, which was partially funded by CCSP-participating agencies. The present synthesis and assessment product on the Arctic and high latitudes will focus on the state of knowledge concerning past changes in the physical climate of this region and the implications of this record of past changes for current and future change. This information is vital since high-latitude regions are projected to continue to experience the greatest warming in the future. Synthesis and Assessment Product 1.3 Reanalyses of Historical Climate Data for Key Atmospheric Features: Implications for Attribution of Causes of Observed Change A reanalysis is a detailed, retrospective study of the state of the atmosphere using a consistent numerical model of the dynamics of the system and based on observations for the time period of the study. This product provides an assessment of the capability and limitations of state-of-the-art climate reanalysis to describe past and current climate conditions, and the consequent implications for scientifically interpreting the causes of climate variations and change. The product will be in the form of a report that summarizes the present status of national and international climate reanalysis efforts, and discusses key research findings on the strengths and limitations of current reanalysis products for describing and analyzing the causes of climate variations and trends that have occurred during the time period of the reanalysis records (roughly the past half-century). The report will describe how reanalysis products have been used in documenting, integrating, and advancing our knowledge of climate system behavior, as well as in ascertaining significant remaining uncertainties in descriptions and physical understanding of the climate system. CCSP Goal 2: Improve quantification of the forces bringing about changes in the Earth’s climate and related systems. Synthesis and Assessment Product 2.1 Scenarios of Greenhouse Gas Emissions and Atmospheric Concentrations, and Review of Integrated Scenario Development and Application This product, which was publicly released in 2007, provides a new long-term, global reference for greenhouse gas stabilization scenarios and an evaluation of the process by which scenarios are developed and used. SAP 2.1 consists of two parts. Part A, Scenarios of Greenhouse Gas Emissions and Atmospheric Concentrations, uses computer-based scenarios to evaluate four alternative stabilization levels of greenhouse gases in the atmosphere and the implications for energy and the economy of achieving each level. Part A includes stabilization scenarios for the six primary anthropogenic greenhouse gases—carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride—and it uses updated economic and technological data and new tools for scenario development. Although these scenarios should not be considered definitive predictions of future events, they provide valuable insights for decisionmakers. Part B, Global Change Scenarios: Their Development and Use, examines how scenarios have been developed and used in global climate change applications, evaluates the effectiveness of current scenarios, and recommends ways to make future scenarios more useful. Part B of the report concludes that scenarios can support decisionmaking by providing insights regarding key uncertainties, including future emissions and climate as well as other environmental and economic conditions. Synthesis and Assessment Product 2.2 North American Carbon Budget and Implications for the Global Carbon Cycle This product provides a synthesis and integration of the current knowledge of the North American carbon budget (including land, atmosphere, inland waters, and adjacent oceans) and its context within the global carbon cycle. In a format useful to decisionmakers, it summarizes knowledge of carbon cycle properties and changes relevant to the contributions of, and impacts upon, the United States and the rest of the world; and provides scientific information for U.S. decision support focused on key issues for carbon management and policy. It addresses carbon emissions; natural reservoirs and sequestration; rates of transfer; the consequences of changes in carbon cycling; effects of purposeful carbon management; effects of agriculture, forestry, and natural resource management; and socioeconomic drivers and consequences. The report includes an analysis of North America's carbon budget that documents the state of knowledge and quantifies uncertainties. Synthesis and Assessment Product 2.3 Aerosol Properties and their Impacts on Climate Aerosols can cause a net cooling or warming within the climate system, depending upon their physical and chemical characteristics. In addition to these direct effects, aerosols can also have indirect effects on radiative forcing of the climate system by changing cloud properties. The first phase of development of this product is to produce major scientific reviews of the following three topics: dependence of radiative forcing by tropospheric aerosols on aerosol composition in the north Atlantic, Pacific, and Indian Ocean regions; measurement-based understanding of aerosol radiative forcing from remote-sensing observations; and model intercomparison to quantify uncertainties associated with indirect aerosol forcing. The second-phase product will draw upon the scientific information gathered by the development of the Intergovernmental Panel on Climate Change Fourth Assessment Report and the National Research Council review, Radiative Forcing of Climate Change. These community-wide assessments of climate change (and the aerosol-climate topic inclusively) will be drawn from in writing SAP 2.3. Synthesis and Assessment Product 2.4 Trends in Emissions of Ozone-Depleting Substances, Ozone Layer Recovery, and Implications for Ultraviolet Radiation Exposure Measurements of ozone-depleting gases in the atmosphere have shown that the concentrations of these gases are declining in response to the agreements reached under the Montreal Protocol. This report will provide an update on trends in stratospheric ozone, ozone-depleting gases, and ultraviolet radiation exposure; progress in improving model evaluations of the sensitivity of the ozone layer to changes in atmospheric composition and climate; and relevant implications for the United States. This information is key in ensuring that international agreements to phase out production of ozone-depleting substances are having the expected outcome—recovery of the protective ozone layer. The report will derive most of its information from recent international assessments of stratospheric ozone, ozone-depleting substances, and climate. CCSP Goal 3: Reduce uncertainty in projections of how the Earth's climate and related systems may change in the future. Synthesis and Assessment Product 3.1 Climate Models: An Assessment of Strengths and Limitations The topics addressed by this product are the strengths and limitations of climate models at different spatial and temporal scales. Its purpose is to provide information on the results from climate models, in ways that will allow the potential user of the information to evaluate how best it may be applied. The product will focus on natural and human-caused factors influencing climate variability and change during the period from 1870 to 2000. It will characterize sources of uncertainty in climate models and their implications for estimating future climate change. This product will be limited to the models and their sensitivity, feedbacks, strengths, and limitations, rather than making specific future projections. Synthesis and Assessment Product 3.2 Climate Projections for Research and Assessment Based on Emissions Scenarios developed through the Climate Change Technology Program This product will have two distinct components. The first will be to produce climate projections for research and assessment based on greenhouse gas emission scenarios and atmospheric concentrations as reported in SAP 2.1a. The second will be to assess the future climate impacts of short-lived gaseous and particulate species. Synthesis and Assessment Product 3.3 Weather and Climate Extremes in a Changing Climate: North America, Hawaii, Caribbean, and U.S. Pacific Islands The impact of climate extremes can be severe and wide-ranging. There is evidence that the economic impact of weather and climate extremes in the United States has increased over the past several decades, but the evidence for increases in extreme weather and climate events varies depending on the event of interest. These events may be related to temperature parameters (severe freezes, heat waves), precipitation (wet spells, heavy precipitation events, droughts, ice and hail, snow cover and depth), or tropical and extratropical storm frequency. Identifying recent changes and trends in such parameters will be a focus of the report, as well as identifying what can be said about future changes. Since extreme weather and climate events on a global scale are regularly addressed in international assessments, this product will focus on weather and climate extremes primarily across Canada, Mexico, and the United States. Synthesis and Assessment Product 3.4 Abrupt Climate Change The paleoclimate record reveals that Earth’s climate can change rapidly and strongly between different stable states. Various scenarios portray future abrupt climate change large enough to pose a significant challenge to society. The goal of this product is to review and synthesize our current understanding of abrupt climate change and to identify gaps in our knowledge. The report will integrate information from the paleoclimate record, the instrumental record, and numerical model-based studies at various spatial scales. Key identified risks, such as changes in ocean thermohaline circulation and alteration of terrestrial hydrologic conditions (e.g., the location or amount of precipitation) will receive special attention because the potential impacts on society are large. CCSP Goal 4: Understand the sensitivity and adaptability of different natural and managed ecosystems and human systems to climate and related global changes. Synthesis and Assessment Product 4.1 Coastal Elevation and Sensitivity to Sea-Level Rise This product will examine the vulnerability of coastal areas in the U.S. mid-Atlantic states to sea-level change. Specific questions to be addressed include identifying which areas are low enough to be inundated by tides, how floodplains would change due to a changing climate, which areas might be subject to erosion, and locations where wetlands will be able to migrate inland versus locations where shores will be protected. The product will examine the implications of sea-level rise, including impacts on population and economic activity in vulnerable areas, costs of shore protection, ecological effects, flood damages, public access to modified shore areas, cases where sea-level rise justifies policy changes, options being considered by conservancies and governments, and lessons from the unfolding consequences of the 2005 hurricanes in the Gulf Coast region. Synthesis and Assessment Product 4.2 Thresholds of Change in Ecosystems There is a body of ecosystems research that focuses on enhancing understanding of climate change impacts on ecosystems (and vice versa) and developing the capability to predict potential impacts of future climate change. Increasing emphasis is being placed on climate-related thresholds that could result in discontinuities or sudden changes in ecosystems and climate-sensitive resources. Discontinuities in responses of ecosystems and resources are difficult to predict, and may significantly affect human societies that depend on ecosystem goods and services. Improved understanding of such sudden changes is essential to managing ecosystems and resources in the face of climate change. This report will synthesize the present state of scientific understanding regarding thresholds of change that trigger sudden changes in ecosystems and climate-sensitive resources. The report will develop a conceptual framework for characterizing sudden changes, and synthesize peer-reviewed studies that provide the best available evidence for defining circumstances that trigger discontinuities in response to climate change. Synthesis and Assessment Product 4.3 The Effects of Climate Change on Agriculture, Biodiversity, Land, and Water Resources This report will address the effects of climate change on agriculture, forestry, land and water resources, and biodiversity. Air and water temperature, precipitation, and related climate variables are fundamental regulators of biological processes. For this reason, human-induced climate change has the potential to affect the condition, composition, structure, and function of ecosystems. Such changes may also alter the linkages and feedbacks between ecosystems and the climate system. Additionally, ecosystems produce a wide array of goods and services valued by humans and in many cases essential for human survival and property. Climate-related changes in ecosystems and other key resources could have impacts on human communities and economic conditions. CCSP Goal 4 (continued) Synthesis and Assessment Product 4.4 Preliminary Review of Adaptation Options for Climate-Sensitive Ecosystems and Resources Climate is a dominant factor influencing the distribution, abundance, structure, and function of, and services provided by, ecosystems. Many ecosystems are thus vulnerable to future changes in climate. The goal of adaptation is to reduce these risks of adverse ecological outcomes through management activities that increase the resilience of these systems to climate change. Resilience is defined here as the magnitude of disturbance that can be absorbed by a system before it shifts from one stable state (or stability domain) to another and the speed of return of a system to equilibrium after a disturbance has occurred. This report will provide a review and synthesis of information on adaptation options for selected climate-sensitive ecosystems in order to aid in designing management strategies that facilitate adaptation, provide examples of how to implement strategies in specific places, and identify issues and challenges associated with implementation of adaptation options. Synthesis and Assessment Product 4.5 Effects of Global Change on Energy Production and Use in the United States This report summarizes what is currently known about potential effects of climatic change on energy production and use in the United States. It focuses on three questions: (1) How might climatic change affect energy use in the United States, (2) how might climatic change affect energy production and supply in the United States, and (3) how might climatic change have other effects that indirectly shape energy production and use in the United States? Great care is being taken in answering these questions, for two reasons. One, the available research literatures on these key questions is limited, supporting a discussion of issues but not providing definite answers. Two, as with many other aspects of potential effects of climatic change on the United States, the effects on energy production and use depend on more than climatic change alone; other potentially important factors include patterns of economic growth and land use, patterns of population growth and distribution, technological change, and social and cultural trends that could shape policies and actions, individually and institutionally. Synthesis and Assessment Product 4.6 Analyses of the Effects of Global Change on Human Health and Welfare and Human Systems Synthesis and Assessment Product 4.6 will examine the effects of global change on human systems. This product will address Goal 4 of the five strategic goals in the CCSP Strategic Plan to "understand the sensitivity and adaptability of different natural and managed ecosystems and human systems to climate and related global changes." The impacts of climate variability, climate change, shifting patterns of land use, and changes in population patterns are human problems, not simply problems for the natural or the physical world. This SAP will examine the vulnerability of human health and socioeconomic systems to global environmental change across three areas of potential impacts and adaptations: human health, human settlements, and human welfare. This product will address the questions of what, where, and when climate variability and change will affect U.S. social systems. The challenge for this project will be to assess risks associated with health, welfare, and settlements and to identify and develop timely adaptive strategies to address human vulnerabilities. The primary goals for adaptation to climate change and variability focus on managing significant risks proactively when possible; establishing protocols to detect and measure risks; and leveraging technical and institutional adaptive capacity to address new climate risks, especially as they exceed conventional adaptive measures. Synthesis and Assessment Product 4.7 Impacts of Climate Variability and Change on Transportation Systems and Infrastructure: Gulf Coast Study This product will address the potential effects of climate variability and change on transportation infrastructure and systems in the central Gulf Coast of the United States. The purpose of this study is to increase the knowledge base regarding the risks and sensitivities of transportation infrastructure to climate variability and change, the significance of these risks, and the range of adaptation strategies that may be considered to ensure a robust and reliable transportation network. Implications for all transportation modes—surface, marine, and aviation—will be addressed. The three-phase study will focus on the Gulf Coast, and will assess the significant risks to transportation, develop methodology to be applied in other geographic locations, identify potential strategies for adaptation, and develop decision-support tools to assist transportation decisionmakers in incorporating climate-related trend information into transportation system planning, design, engineering, and operational decisions. CCSP Goal 5: Explore the uses and identify the limits of evolving knowledge to manage risks and opportunities related to climate variability and change. Synthesis and Assessment Product 5.1 Uses and Limitations of Observations, Data, Forecasts, and Other Projections in Decision Support for Selected Sectors and Regions The product will focus on characterizing a subset of the observations from remote-sensing and in situ instrumentation that are of high value for decisionmaking. The product will characterize observational capabilities that are currently or could potentially be used in decision-support tools, catalog a subset of ongoing decision-support activities that use these capabilities, and evaluate a limited number of case studies of these decision-support activities. The detailed evaluation of decision-support activities and demonstration projects will provide information to agencies and organizations responsible for developing, operating, and maintaining selected decision-support processes and tools. The evaluation will also provide information on the nature of interactions between users and producers of climate science information, approaches for accessing science information, and assimilation of scientific information in the decisionmaking process. The product will include an online catalog of decision-support demonstration projects with interactive links, which will be updated as additional experiments are conducted and new approaches to incorporating and benchmarking application of observations and other global change research products evolve. Synthesis and Assessment Product 5.2 Best Practice Approaches for Characterizing, Communicating, and Incorporating Scientific Uncertainty in Climate Decisionmaking This product will address the issue of uncertainty and its relationship to science, assessment, and decisionmaking. Specifically, the product is intended to help improve the quality and consistency of information about scientific uncertainty presented to decisionmakers and other users of CCSP reports by identifying "best practice" options recommended in the literature on this subject; to improve communication between scientists and users of the products by providing recommendations for addressing uncertainty; and to provide a brief overview of the literature on approaches for communicating and considering uncertainty related to climate. Synthesis and Assessment Product 5.3 Decision-Support Experiments and Evaluations Using Seasonal-to-Interannual Forecasts and Observational Data This product will concentrate on the water-resource management sector. It will describe and evaluate current forecasts, assess how forecasts are being used in decision settings, and evaluate decisionmakers’ level of confidence in these forecasts. The participants in the development of this product (primarily consisting of government officials, researchers, and users) will evaluate forecasts as well as their delivery, to identify options for improving partnerships between the research and user communities. It will inform decisionmakers about the experiences of others who have experimented with the use of seasonal and interannual forecasts and other observational data; climatologists and social scientists about how to advance the delivery of decision-support resources that use the most recent forecast products, methodologies, and tools; and science managers as they plan for future investments in research related to forecasts and their role in decision support.

Decision Support Goal 2: Adaptive Management and Planning Decisions

Decision Support Goal 3: Methods to Support Climate Policymaking

CCSP also supports the development of integrated modeling frameworks that are useful for exploring many dimensions of climate and global change. Full integration of information on human activities, greenhouse gases and aerosol emissions, land-use and land-cover change, cycling of carbon and other nutrients, climatic responses, and impacts on people, the economy, and resources is necessary for analysis of many important questions about the potential economic and environmental implications of changing greenhouse gas concentrations and alternative technology portfolios. Answers from integrated analysis can only reflect the existing state of knowledge, but it is important to develop frameworks and resources for integration, exercise them, and learn from analysis of the results. CCSP is encouraging innovation and development of approaches to integrated analysis.

See also: Human Contributions and Responses to Environmental Change [also available: PDF Version]. Chapter 9 from the Strategic Plan for the Climate Change Science Program (July 2003). Human Contributions and Responses to Climate Change.  Presentation from Breakout Session 9 of the US Climate Change Science Program: Planning Workshop for Scientists and Stakeholders, 3-5 December 2002, Washington, DC.