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The Kyoto Earth Summit recently ended, amid substantial disagreement over current and future global change, and their significance to humankind. The core of the problem is that many global leaders are unconvinced that significant global change is now occurring. Further, there is insufficient confidence in the accuracy of global-scale computer models that project future changes to initiate the political and economic re-directions that would be required to alleviate the problem. As was first said years ago, we are conducting the first global-scale biogeochemistry experiment, the outcome of which is not known, and which could severely impact the habitability of the planet. Conversely, any meaningful reduction in fossil fuel consumption will require the redirection of trillions of dollars of the world economy. The decision to embark on a serious redirection of world energy consumption is, along with population control, possibly the most fundamental global policy of the next century.

This revision maintains the position of Forest Ecosystems as the one source for the latest information on the advanced methods that have enhanced our understating of forest ecosystems. Further understanding is given to techniques to explore the changes in climatic cycles, the implications of wide-scale pollution, fire and other ecological disturbances that have a global effect. The inclusion of models, equations, graphs, and tabular examples provides readers with a full understanding of the methods and techniques.* Includes a revised section on important advances in regional scale analyses * F

In this report we evaluate adaptation issues for natural ecosystems. We will specifically focus on the interactions with the abiotic environment of plants and animals, along with other organisms with which they interact (e.g., disease-causing bacteria and viruses). We further limit ourselves to natural ecosystems in which the predominant vegetation has developed without having been planted, irrigated, or fertilized. Most of the natural lands in the United States are managed by federal or state governments. Agricultural lands— including range grazing lands — are dealt with in a related adaptation report. This will evaluate the potential magnitudes and challenges facing terrestrial ecosystems in the United States in adapting to changing climate over the next 30-50 years. Our report will not address attribution or mitigation of climate change, as these topics have been dealt with in many other forums. We will begin with a brief summary of the current trajectory of the changing climate in the United States, including both temporal and spatial patterns. We will then relate these trends to ecosystem impacts and vulnerabilities.

Accurate monitoring of global scale changes in the terrestrial biosphere has become acutely important as the scope of human impacts on biological systems and atmospheric chemistry grows. For example, the Kyoto Protocol of 1997 signals some of the dramatic socioeconomic and political decisions that may lie ahead concerning CO2 emissions and global carbon cycle impacts. These decisions will rely heavily on accurate measures of global biospheric changes Schimel 1998 and IGBP TCWG 1998. An array of national and international programs have inaugurated global satellite observations, critical field measurements of carbon and water fluxes, and global model development for the purposes of beginning to monitor the biosphere. The detection by these programs of interannual variability of ecosystem fluxes and of longer term trends will permit early indication of fundamental biospheric changes which might otherwise go undetected until major biome conversion begins. This article describes a blueprint for more comprehensive coordination of the various flux measurement and modeling activities into a global terrestrial monitoring network that will have direct relevance to the political decision making of global change.

Quantitative models are crucial to almost every area of ecosystem science. They provide a logical structure that guides and informs empirical observations of ecosystem processes. They play a particularly crucial role in synthesizing and integrating our understanding of the immense diversity of ecosystem structure and function. Increasingly, models are being called on to predict the effects of human actions on natural ecosystems. Despite the widespread use of models, there exists intense debate within the field over a wide range of practical and philosophical issues pertaining to quantitative modeling. This book--which grew out of a gathering of leading experts at the ninth Cary Conference--explores those issues. The book opens with an overview of the status and role of modeling in ecosystem science, including perspectives on the long-running debate over the appropriate level of complexity in models. This is followed by eight chapters that address the critical issue of evaluating ecosystem models, including methods of addressing uncertainty. Next come several case studies of the role of models in environmental policy and management. A section on the future of modeling in ecosystem science focuses on increasing the use of modeling in undergraduate education and the modeling skills of professionals within the field. The benefits and limitations of predictive (versus observational) models are also considered in detail. Written by stellar contributors, this book grants access to the state of the art and science of ecosystem modeling