Prior to beginning graduate school, Kelsey Foster was studying methane emissions from anthropogenic sources within California. Her focus was on understanding the complexities of methane emission sources at oil refineries. Since starting her Ph.D., she has shifted her research focus to studying how uncertainty in estimates of carbon uptake by vegetation vary across different spatial scales. Her main research interests are in understanding how different components of the Earth system are responding to increased greenhouse gas emissions and how integrating multiple data sources can enhance our understanding of major sources of emissions.