Enhancing Productivity and
Resilience of Natural Resources

[ Climate Variability and Agriculture in the Southeast United States ]
[ Energy Efficiency of Businesses ]
[ IPCC (Intergovernmental Panel on Climate Change) Working Groups ]
[ Transboundary Fisheries: Pacific Salmon ]
[ Uncertainty Analysis for Climate Change and Its Impacts ]
[ Water Resources and Climate Change ]
[ Will Tropical Forests Survive the Twenty-First Century? ]
[ US National Assessment ]
[ Yangtze Delta in China as Evolving Metro-Agro-Plex ]


Climate Variability and Agriculture
in the Southeast United States

Research on three overlapping multi-year projects (NASA/USEPA/USDA) has continued by Linda Mearns, Richard Katz, Larry McDaniel, Elena Tsvetskinskaya, Gregory Carbone (U South Carolina), Bette Walter-Shea (U Nebraska), and William Easterling (Pennsylvania State U). Regional climate modeling and conditioned stochastic modeling form the basis of several different types of climate change scenarios. Remote sensing, crop and economic model, and spatial scaling analysis make up the other elements of the projects. Major accomplishments in the projects during FY00 include:

  • Production runs of six different crop models with and without direct CO2 effects and with adaptation, using a baseline climate data set and the two different resolution climate scenarios on a baseline grid of 0.5 by 0.5 degrees, calculation of percentage changes in yield (from baseline), and comparison of these for the coarse and fine scenarios;
  • Application of an additional cotton model, GOSSYM;
  • Application of complex spatial statistics to determine significance of contrast in mean and spatial patterns of yields;
  • Production of two different resolutions scenarios for the rest of the United States (with a coarser baseline grid);
  • Application of the yield results to an agricultural sector model (ASM);
  • Advanced work on remotely sensed AVHRR and SPOT data; and
  • Analysis of observed temperature and precipitation data sets in the Southeast United States for development of stochastic models conditioned on the Bermuda High Index. (For more information, see the last paragraph in this section on "Statistical Downscale of Weather Generators."

Highlights of Results: We found that significantly different changes in most yields resulted from the two different scenarios, when calculated on the common 50-km grid of the regional climate model for the case of climate change only, climate change plus CO2, and adaptation effects [ South East Mean Dryland Yield Comparisons ]. In the climate-change-only case, for most crops, yield decreased for the two scenarios, but decreases were greater when determined from the regional climate scenario [ Simulated Yields For Dry Land Corn ]. Mearns and colleagues then aggregated the yield results to the economic units (usually states) required for use in the ASM and found that for some states the significantly different results persisted. The economic model was run for the base case and for the two climate-change-plus-direct-CO2 cases.

For the country as a whole, the coarse-scale scenario resulted in increased total surplus for the agricultural sector ($2.55 billion), but the fine-scale scenario produced a small decrease (-$0.16 billion). Regional index numbers for the total value of production, which is a measure of economic activity within the regions, show interesting contrasts across the regions, based on the scenarios [ Regional Index Numbers for Total Value of Production ]. The southeast and Appalachian regions show the largest decreased in activity for both scenarios, but the decrease with the fine-scale scenario is much larger. Results indicate that the scale of climate change scenario substantially affects the simulation of changes in crop yields on various levels of spatial aggregation. These results further confirm the earlier results of Mearns et al. (1999, 2000), but for a larger region and a greater variety of crops. Moreover, Mearns and colleagues have demonstrated that these contrasts in changes in yield are substantial enough to affect the results of an agricultural economic model, both on national and regional levels.

Statistical Downscale of Weather Generators: The goal of this research is to develop improved statistical methodology for generating climate change scenarios at local/regional spatial scale and on daily time scales conditional on large-scale circulation patterns. In collaboration with Marc Parlange (Johns Hopkins U) and Claudia Tebaldi (formerly NCAR/GSP), Richard Katz continued work on the development of stochastic weather generators for locations in Southeast United States conditional on indices of large-scale atmospheric/oceanic circulation (especially the so-called Bermuda High). During the past year, innovative statistical methods were developed to better identify which aspects of daily weather variables (e.g., means, variances, and autocorrelations) depend on the indices.

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Energy Efficiency of Businesses

John Firor is involved in a joint project with colleagues at the University of Colorado-Denver that aims at educating CEOs of large Colorado companies concerning the opportunities for increasing profits by becoming more energy efficient. This process also decreases the country's emissions of greenhouse gases. With a grant from the Energy Foundation, the project retained the services of an energy efficiency expert to work with the companies to ascertain their needs and to recommend next steps. Ten companies have agreed to participate in the program. The project also expects that the demonstration of success by these companies will enlighten the Colorado congressional delegation concerning the existence of "non-regret" or "win-win" opportunities for decreasing greenhouse gas emissions.

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IPCC (Intergovernmental Panel on Climate Change)
Working Groups

Kathleen Miller and Stewart Cohen (Environment Canada) are co-Convening Lead Authors of the chapter on "North America," for IPCC Working Group II, Third Assessment Report (to appear in FY01), which provides an assessment of potential climate change impacts in the United States and Canada. Miller has written sections of the chapter, helped to coordinate responses to reviewer comments, and collaborated with the lead authors to complete the final revisions on this chapter.

Linda Mearns is co-convening Lead Author of Chapter 13, "Climate Scenario Development" with Michael Hulme (U East Anglia, Norwich, UK) in the Working Group I report of the IPCC Third Assessment Report (to appear in FY01). This chapter acts as an important bridge between the climate science of Working Group I and the Climate Impact Science of Working Group II. She is also a Lead Author of Chapter 10, "Regional Climate Analysis," of the Working Group I Report, which assesses regionalization techniques such as statistical downscaling, regional climate modeling, and stretched GCM grid techniques. A paper on the regional results of new OGCM projections is in preparation to Nature. Mearns is also a contributor to Chapter 9, "Climate Change Projections." In Working Group II, she is a Lead Author of Chapter 3, "The Development and Application of Scenarios in Climate Change Impact, Adaptation and Vulnerability Assessment." This is another new chapter for the Third Assessment Report, which discusses and integrates all types of scenarios needed for performing climate change impacts and integrated assessments. It acts as the other half or the bridge between Working Groups I and II. During FY00, the second, third, and final drafts of these chapters were completed.

Both Miller and Mearns traveled extensively during FY00 in support of the IPCC. Mearns also continued her participation on the IPCC Task Group for Formation of Climate Change Scenarios for Impacts Assessment. This group develops guidance material for the use of climate change scenarios and maintains the Data Distribution Center, from which impacts scientists can obtain a range of state-of-the-art global climate change scenarios.

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Transboundary Fisheries: Pacific Salmon

Kathleen Miller is the co-Principal Investigator of this NOAA/OGP-funded project, working with Robert McKelvey (Professor Emeritus, Mathematics, U. Montana) and Gordon Munro (Professor Emeritus, Economics, U. British Columbia). Pacific salmon are anadromous fish that cross state and international boundaries in their oceanic migrations. The history of attempts by the United States and Canada to cooperatively manage their respective salmon harvests suggests that environmental variability may complicate the management of such shared resources. Miller published one paper during FY00 in Climatic Change, "Pacific Salmon Fisheries: Climate Information and Adaptation in a Conflict-Ridden Context," describing the history and sources of the conflict. Miller and colleagues prepared another paper that draws lessons from the recent period of turmoil to identify strengths and weaknesses in the new abundance-based management approach, and to suggest avenues for further negotiations to secure more rational management of Pacific salmon resources. This paper, "Climate, Uncertainty and the Pacific Salmon Treaty: Insights on the Harvest Management Game," will be published in FY01 in Proceedings of the International Institute of Fishery Economics and Trade.

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Uncertainty Analysis for Climate Change and Its Impacts

The goal of this research is to review tools that have been employed in performing uncertainty analysis for climate change scenarios and impact studies. Richard Katz's working during the past year focused on identifying recent developments in statistics that could enable more full-fledged uncertainty analyses to be performed as part of integrated assessments of climate change and its impacts.

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Water Resources and Climate Change

Columbia River Water Resources. Global climate change could have significant impacts on natural resource ecosystems. Kathleen Miller, along with collaborators at Environment Canada (Vancouver, British Columbia) and the University of Washington, completed a project during FY00 designed to examine scenarios of global climate change and resource management in the Columbia River Basin. Scenario changes in natural streamflow were estimated using a basin hydrology model. The authors also held interviews with water managers and other stakeholders in the Canadian portion of the basin. A paper appeared in the June 2000 issue of Water International as a result of this project (Cohen et al.).

Great Plains Water Resources. Climate change in the Great Plains region may have profound effects on agricultural users, aquatic ecosystems, and urban and industrial users alike. The potential impacts of climate change include changes in winter snowfall and snowmelt, growing season rainfall amounts and intensities, minimum winter temperature, and summertime average temperature. The combined effect of these changes in weather patterns and average seasonal climate will affect numerous sectors critical to the economic, social, and ecological welfare of this region. Miller and colleagues have published a paper in the December 1999 Journal of the American Water Resources Association, "Potential Climate Change Impacts on Water Resources in the Great Plains" (Ojima et al.). This paper calls for research to better address the current competition among the water needs of agriculture, urban, and industrial uses, as well as the effect of climate change on the natural ecosystems of the Great Plains.

Water Resources in the Intermountain West. The climate of the West continues to play a role in the developing western economy. Much of the West is arid, and climate is one factor attracting a new wave of migration into the region. However, limited water supplies create tensions between the "old West" that was built on irrigated agriculture and the "new urban West." Miller has submitted a paper, "Climate and Water Resources in the West: Past and Future," which will be included in a special issue of Journal of the West on Climate in the West, edited by Kenneth Dewey (U Nebraska), to appear in FY01. This paper discusses the role of climate and streamflow characteristics in the historical development of water resources in the western United States, and the challenges presented by changing demands on water resources coupled with the possible impacts of climate change. Miller and Steven Gloss (U Wyoming) have also prepared a paper on "Climate Variability and Water Resources in the Interior West: Social, Policy, and Institutional Issues," which has been submitted for publication by Island Press. This paper deals with climate variability in the region over the past several decades. The authors argue that research on effective policy and institutional arrangements is necessary to take advantage of recent scientific and technical advances in predicting the nature and extent of climate variability.

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Will Tropical Forests Survive the Twenty-First Century?

The need for accurate estimates of forest cover and of forest fragmentation is a critical issue for developing countries such as Costa Rica, which holds between 4% to 5% of all biodiversity in the world. In this study, Robert Harriss and colleagues provide comprehensive and accurate estimates of forest cover for Costa Rica using LANDSAT-5 Thematic Matter satellite scenes acquired between 1986 and 1991. This study concludes that:

  • In 1991, 29% (~14,000 km2) of the land cover of Costa Rica was evergreen forest cover. Of that forested area, approximately 30% is protected by national conservation policies.
  • Forest loss in a study area representing 93% of Costa Rica's territory during a five-year period (1986-1991) was 2,250 km2, and the estimated deforestation rate of ~450 km2 per year or ~4.2% per year of remaining forest cover.
  • Tropical forests are almost completely eliminated from the moist tropical and moist premontane forest life zones.
  • The level of forest fragmentation in remaining forested areas may be more advanced that previously understood.

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US National Assessment

Linda Mearns is a member of the National Agricultural Sector Team, US National Assessment. During FY00, she gave presentations on the role of extreme events in agriculture at various team workshops and is a major contributor to the Report of the Agriculture Sector, particularly the chapter on climate variability and crops. A paper has been submitted to Science on the Agriculture Sector results. She is also a member of the Climate Change Scenarios Writing Team for the Assessment. On a regional level, she is a member of the Assessments Teams for the Southwest Region and the Rocky Mountain Basin and Range Region. On both teams, she has provided advice on development and use of climate change scenarios and has contributed to both Regional Assessment Reports.

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Yangtze Delta in China as Evolving Metro-Agro-Plex

A three-year project funded by NASA continued on this subject during FY00. Linda Mearns, Larry McDaniel, Filippo Giorgi (CGD/Trieste Institute of Physics, Italy) and Wei Gao (NREL, Fort Collins) worked in collaboration with Bill Chameides (Georgia Institute of Technology). This is an international, multidisciplinary research project focusing on the effects of regional environmental change on agriculture in China, the most populous and rapidly developing nation in the world. The project includes the assessment of major pollutants (ground-level ozone, nitrogen oxides, gaseous sulfur oxides) and their effects on present-day and future agriculture yields of crops, as well as the effects of particulate emissions and land-use changes on the regional climate in China and their concomitant impact on future agricultural yields. Mearns and colleagues primarily modeled wheat and rice crops for the region, using CERES and UCLA-YIELD crop models. The CERES wheat and rice models were validated and tested for locations within the Yangtze River Delta using data supplied by colleagues at the Jiangsu Academy of Agricultural Sciences in Nanjing, China. Sensitivity analyses of the crop model responses to decreased solar radiation have been performed. Decreases in solar radiation occur in the region due to heavy sulfate emissions. Results indicate that a ten percent increase (decrease) in solar irradiance produces about a ten percent increase (decrease) in simulated wheat yields. A similar linear response was found for rice (percentage change in crop yields). A paper appeared in the Proceedings of the National Academy of Sciences during FY00 covering the effects of decreased solar radiation on wheat and rice.

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