Ecosystems are defined by dynamical interactions between groups of organisms, the communities they constitute, and the physical and chemical conditions and processes occurring in the environment. These dynamics are complex and multiscale across both length and time. This course will explore quantitative approaches that observe, measure, model, and monitor ecosystems and the services that they provide society-and the emerging opportunities that could employ these approaches to improve and strengthen global sustainability when it comes to our own ecology. This course will feature lectures each week from different members of the Caltech faculty working on ecological problems from different angles in order to illustrate how fresh insights can emerge by drawing on diverse ways-of-knowing. Given in alternate years; not offered 2022-23.