The environment on our planet has evolved on geologic timescales in response to variations in solar input, planetary albedo, and the trace gas content in our atmosphere. Investigation of how the climate has changed, and how the planet has responded to these changes, establishes the backdrop for the rapid change now occurring. Global change research in the Geological Sciences department at CU quantifies these changes using information extracted from geological archives that range from ice cores to marine sedimentary deposits to geomorphic features on the landscape. We maintain a wide array of laboratories in both the Benson Geological Sciences building and the newly completed Sustainability, Energy and Environmental Laboratory (SEEL), with instruments capable of measuring elemental and isotopic concentrations that serve either as direct measures or as proxies for environmental variables through time.