ENV 210A offers an introduction to the scientific and technological dimensions of the nexus of global environmental problems: climate change, the carbon cycle, biodiversity loss, and food and water for 9 billion people. The course will provide students the scientific foundations to understand each of these complex environmental problems, first in isolation and then in its interaction with the others. By the completion of the course, students will be able to understand major scientific reports on the interacting environmental challenges of the 21st century. All sections of ENV 210A will meet together for lecture and precept each week.