Focuses on the cycling of elements at the global scale with a particular emphasis on human modification of biogeochemical cycles. Major biogeochemical cycles, their past dynamics, present changes, and potential future scenarios will be addressed. Ecosystem to global-scale model of the earth system will be discussed, along with global-scale measurements of element fluxes from satellites, aircraft, and measurement networks. Prereq., general chemistry, some organic chemistry. Same as GEOL 5305. Prerequisites: Restricted to Graduate Students only.