California's extraordinary ecological and economic diversity has brought it prosperity, pollution, and overpopulation. These factors, together with the state's national and international ties, make California an essential test case for the impact of global climate change - temperature increases, water shortages, more ultraviolet radiation. Ecological and economic changes that affect California's widely envied individualistic culture will have far-flung repercussions. Global climate change became a worldwide concern during the late 1980s as scientists debated the implications of observed ozone depletion and "greenhouse gas" concentrations, or projected us into the twenty-first century by means of complex computer simulations. Even though many questions remain unanswered, the scientific community is largely convinced that changes - possibly momentous - in the earth's climate are now underway. In this forward-looking volume some highly qualified scientists give their best estimate of what the future holds. Beginning with an overview by Joseph Knox, the authors discuss the greenhouse effect, the latest climate modeling capabilities, and the implications of climate change for California water resources, agriculture, biological ecosystems, human behavior, and energy. The warning inherent in a scenario of unchecked population growth and energy use in California clearly applies to residents of the entire planet. The sobering conclusions reached by these scientists include specific recommendations for research that will help all of us plan and prepare for potential climate change.