My primary research focus is on physical-biological interactions in the ocean and their connections to climate, particularly in the northeast Pacific. Recently, I have focused on interannual to decadal scale variability in the physical ocean environment off the US West Coast, its relationship to known modes of climate variability (e.g. ENSO) and long-term climate change, and the potential impacts of this variability on phytoplankton and higher trophic levels. I rely heavily on numerical ocean models in my research, and also leverage observational data from satellites, ships, and autonomous ocean platforms, depending on the problem at hand.


In terms of global primary production (conversion of carbon dioxide to organic matter), the contribution of phytoplankton in the ocean (shown in green) is approximately 50%, equal to that by all plants on land. However, direct measurement of oceanic productivity is neither easy nor routine. Over the past three decades there have been ongoing efforts to improve productivity estimates from satellites, though they remain inherently limited by the inability of satellites to see below a shallow surface layer. My research shows that we can greatly improve productivity estimates by combing data from autonomous underwater vehicles such as ARGO floats and underwater gliders. These platforms (shown in yellow) are an important bridge between accurate but sparse shipboard measurements and abundant but uncertain satellite estimates.


Due to the expense and scarcity of carbon dioxide (CO2) sensors, there has been a push over the past decade to reduce their cost and size while maintaining the requisite accuracy and precision. I spent several years developing and deploying novel CO2 instruments designed for specific research platforms, including aircraft, ships, and autonomous air and water vehicles (right). The oceanic component of this work was conducted in Monterey Bay, California, largely in collaboration with the Monterey Bay Aquarium Research Institute, and included participation in the Monterey Bay 2008Monterey Bay 2010, and COAST field campaigns, as well as installation of a CO2 sensor as a new component of the Santa Cruz Ocean Observing Platform (SCOOP).