An Overview of Ecological Crises

Environmental systems are complex and interwoven with human society and economies. We depend on the earth for our habitats, resources and health, and yet we often treat it as if it were external to us. In this course you will learn the extent and scale of the ecological crises facing us. The course introduces the concept of planetary boundaries — the limits that various earth systems can handle while retaining their function and stability. Climate change, including atmospheric carbon dioxide, is one such boundary, but it is far from the only environmental crisis facing our world. Biodiversity loss and the degradation of biosphere integrity, coupled with land overuse, pose as serious a threat as a changing climate and interacts with climate change to compound both risks. Furthermore, there are threats caused by crossing other boundaries, such as freshwater overuse, overproduction and introduction to the environment of novel entities (such as microplastics and “forever chemicals” like PFAS) and out-of-balance phosphorus and nitrogen flows largely driven by fertilization practices in industrial agriculture. This course shows that our current ways of producing and consuming cannot endure and that some degree of loss is inevitable. We will explore the root causes of these environmental crises and zoom out to look at the complex systems driving us across planetary boundaries. You will also see the ways in which these changes are not equally distributed, and that in fact many of those who are least responsible for ecological crises are already bearing — and will continue to bear — the most extreme consequences.