While retaining the chapter sequence and basic structure of the original version, this edition has been thoroughly updated with the most recently available data. We use the latest current events to show how environmental science principles can be used to analyze problems and find solutions to pressing problems. Among the most important changes in this edition are:

Chapter 1 A major revision enhances this chapter with a discussion of science and it's practice, including the scientific worldview, scientific design, the importance of statistics, reproducibility and significance, sample size, blind and double blind experiments, cooperation and insight in science, and additional examples of inductive reasoning. A brief overview of conservation history has been added to this chapter to give students a sense of how the field has developed.

Following a section on pseudoscience and baloney detection, we offer a critical thinking box on the controversy engendered by Danish political scientist, Bjorn Lomborg's book The Skeptical Environmentalist. We present both pro and con sides of this debate so students can form their own opinions about this issue.

Chapter 2 Following reviewers' suggestions, we have rewritten the entire section in this chapter on environmental chemistry to eliminate errors and improve coverage. The hydrological cycle has been moved into this chapter so it can be discussed together with other biogeochemical cycles. An updated and corrected periodic table is presented in figure 2.2.

Chapter 3 Again, following reviewers' comments, we have strengthened and expanded our discussion of evolution to include effects of positive and negative mutations, geographic and behavioral isolation, and to tie competition to tolerance range and critical ecological factors. The classic snowshoe hare/ Canadian lynx story of predator/prey relations is updated to include modern questions about how data was collected.

Chapter 4 Using the most recent information from the Population Reference Bureau and the United Nations Population Division, graphs, charts, and tables in this chapter have been revised with up-to-the-minute data. The chapter opens with a vignette about population growth in India and conflicts about the best way to reach stability.

Chapter 5 In response to requests from reviewers, we've added a section on marine ecosystems to the biome discussion, and improved the explanation of climate graphs in Fig. 5.4.

Chapter 6 Drawing on the 2002 FAO report--State of the World's Forests, we have updated information on tropical and temperate forest area and rates of deforestation. New tables and graphs show rates of loss by region and by source.

The hot, dry summer of 2002 resulted in large forest fires in the western United States. Competing ideas about how forests should be managed and fires could be suppressed or prevented provide an opportunity to examine resource policies and practices. The highly controversial issue of logging in roadless, defacto wilderness areas also is discussed. Ecosystem management has become the operative paradigm of several U.S. resource agencies, so we've added a section on this topic. Contentious issues of park and wildlife refuge area management also are discussed.

Marine refuges and reserves are being declared by a number of nations. Research shows that a ban on fishing in refuges can increase fish populations significantly in adjacent areas. We review some of the important developments in this subject.

Chapter 7 Reports prepared for the 2002 World Summit on Sustainable Development in South Africa provide data for a major revision of this chapter on world food supplies and food security issues. Controversial topics such as livestock confinement operations, availability of irrigation water, and the pros and cons of pesticides and organic farming are also included. A new case study illustrates the ways in which shade-grown coffee and cocoa can help protect biodiversity.

A major new section on genetic engineering and the debate over ecological and human health safety of genetically modified organisms is added to this chapter. Coverage of this controversial topic is balanced and objective, giving students information with which to form their own opinions. Without going too deeply into either genetics or biochemistry, students are taught some basic biology about genetic modifications that will help them understand this complex but important topic.

Chapter 8 Following the tragic events of September 11, 2001, we all must become better informed about the risks of terrorists attacks. This chapter opens with a vignette about the potential for bioterrorism. This leads into a newly revised discussion of infectious diseases and environmental health hazards that help understand how diseases can spread and what factors present the greatest risk. Newly published data on leading causes of death and disability put these risks in perspective.

Another important environmental health topic is emergent diseases-those that were previously unknown or which have been dormant for many years but suddenly reappear. We expand this important coverage to include emergent ecological diseases such as chronic wasting disease in deer and elk, black band disease of corals, and the widespread deaths of North Atlantic marine mammals.

A boxed reading on the statistical significance of disease clusters-using the recently announced contraction of Parkinson's disease by actor Michael J. Fox and several of his coworkers as an example-will interest students looking for patterns in environmental diseases.

Chapter 9 Many environmental scientists regard global climate change as the most important issue facing us today. Drawing on recently published reports of the Intergovernmental Panel on Climate Change, this chapter has been extensively revised and updated to reflect current information on this important topic. Opening with a compelling vignette of recent evidence of global warming, the chapter goes on to a thorough and detailed discussion of climate models and projections for possible effects of climate change. Some of the basic science underlying this debate is revealed in a new box on satellite imaging and how it is used in climate analysis. Policy choices for reducing climate change are explored, including reducing emissions, changing to new energy sources, and storing carbon dioxide. Critical thinking on this issue is encouraged by a new boxed reading on scientific uncertainty and general circulation models.

Chapter 10 Again drawing on preparatory material for the Johannesburg World Summit on Sustainable Development, this chapter presents a wealth of information on world water supplies and impending shortages. The opening vignette on the Three Gorges Dam illustrates both the promise and the dangers of intrabasin water transfers. A fascinating case study of the controversy around water diversion projects on the Klamath River in California shows how these principles apply at home as well as abroad.

A greatly expanded box on water quality testing will help students understand both the major types of water pollutants and how they are analyzed. This information compliments new data on water quality assessments in U.S. rivers and lakes by the Environmental Protection Agency.

Chapter 11 This chapter opens with a vignette concerning another highly controversial current issue, the storage of high-level radioactive waste at Yucca Mountain, Nevada. An unusual aerial photograph of Yucca Mountain gives an interesting perspective on why it was chosen as a nuclear waste repository. Using questions about the geological stability of Yucca Mountain illustrates how geology is important in environmental science. After reviewing some basic geology, the chapter discusses current issues in economic mineralogy and resource extraction such as mountain top removal in Appalachia and heap-leach mineral extraction techniques.

Chapter 12 Opening with a discussion of proposed oil and gas drilling in the Alaska National Wildlife Refuge, this chapter presents a detailed examination of the pros and cons of both traditional (fossil fuels and nuclear power) and renewable energy sources such as wind, solar, fuel cells, and geothermal energy. Many students will be unaware that unconventional fossil fuel reserves such as tar sands and oil shales could potentially contain far more energy than liquid oil supplies. The environmental effects of extracting and using these sources, however, require careful consideration.

This chapter ends with energy scenarios just published in 2002 by the World Energy Council as a tool for envisioning future developments. The chapter also reviews some of the controversy surrounding Vice President Dick Cheney's Energy Policy Task Force and it's vision of our energy future.

Chapter 13 New data on waste production and recycling rates bring this chapter up to date. Recycling successes and challenges are discussed including recent bans on single use beverage containers and requirements for recycling of computers and automobiles in Europe. A new boxed reading on bioremediation explores alternative methods for cleaning up toxic wastes.

Chapter 14 Sustainable development is a major international focus and a key theme in this book. To understand this topic, students need some background in ecological economics, which we present in this chapter. By 2050, two-thirds of the world population is expected to live in urban areas. Thus, most economic development and progress towards sustainability will have to occur in cities. To appreciate both the promise and problems of urban areas, we include a brief overview of city planning. Urban blight, sprawl, and smart growth receive a more thoughtful and contemporary treatment in this chapter than in any other environmental science textbook on the market. A new boxed reading on urban ecology illustrates the environmental quality of these issues; while a web exercise in calculating ecological footprints at the end of chapter helps students apply urban issues to their own lives.

Chapter 15 A unique feature of this book is its systematic and meaningful presentation of environmental policy. This section has been strengthened and made even more thorough with the addition of information on science and policy in local communities. It also has updated information on international bodies and conventions such as the World Trade Organization, the World Bank, and the North American Free Trade Agreement.

New photographs and art Approximately 60 new full color photographs help maintain student interest by showing real life examples of environmental issues. In addition, 34 new or revised graphs, drawings, and other graphics provide valuable information as well as making the text attractive and highly readable. Ten new tables allow readers to compare and understand data in greater depth than just what is provided by straight text.

New case studies, opening stories, and other special readings Every chapter starts with an opening vignette that presents a fascinating current environmental problem that illustrates the principles to be presented in the text. Interspersed throughout each chapter are other special features that show concrete application of theoretical knowledge. Ranging from controversy over dredging PCBs from the Hudson River to the threat of bioterrorism, these special readings also provide an opportunity to bring up current events and to make connections to real-life issues. Of the 30 special readings in the book, 16 are new to this edition, making the text thoroughly up to date and relevant.