ENV 595 (Global Environmental & Climate Change)
Unlike any other species in Earth history, the human species has had a profound impact on each of Earth's spheres—its atmosphere, hydrosphere, geosphere and biosphere. Although researchers in many scientific disciplines have documented natural paleo-environmental change, recent human activities have led to environmental change at rates that are unprecedented at times in the past. For example, geologists, atmospheric chemists and others have documented the natural buildup of carbon dioxide in Earth's atmosphere during warm periods in Earth history (interglacials), with much reduced levels during glacial periods. As a "greenhouse gas", carbon dioxide traps longwave radiation, causing a general heating of our atmosphere. Though the relationships are not completely understood, profound changes in biotic distributions, climatic patterns, distribution of surface water, sea levels, etc., have occurred at the same time. Recent evidence suggests that accumulation in the atmosphere of large amounts of carbon dioxide and other gases due to burning of fossil fuels has the potential to accelerate the warming process by at least an order of magnitude over natural rates in the past. The effect on other aspects of our ecosystem could be substantial.
In this course we examine 1) the nature of human impact on atmospheric composition and our environment, and the consequences of greenhouse gas accumulation in determining environmental and climatic change; 2) the geologic record of analogous events, which are important in our examination of the non-anthropogenic mechanisms of climate change, and 3) the policy and management implications of climate change. Although we tend to believe that changes in the Ecosphere (whole Earth) occur slowly over time, recent evidence suggests quite the opposite: changes can occur over the course of decades, or during the lifetime of a single individual.
Most predictions on the effects of global changes have been based on either analogous climates from times in the geologic past, or complicated computer models. We will evaluate the differences between the two methods, and the assumptions, sensitivities, applications and deficiencies of the models that are currently used. We will pay special attention to the role of paleoenvironmental data in model development and validation.
Course Objectives and Outcomes
To introduce students to the problems facing human and natural systems in the future; to allow students to practice oral and written communication; to practice critical thinking skills.