Grant: Discovery Grants Program - Individual

Phytoplankton account for about 50% of global primary production and they drive a flux of carbon from the atmosphere to the deep ocean. This carbon flux is responsible for about 11 Gt C a-1. This is a significant flux of C as it is currently larger than the annual anthropogenic input of C into the atmosphere. Changing climate at the surface of the ocean, including temperature, atmospheric CO2, ocean pH, and wind-driven mixing, will alter the distribution of phytoplankton biomass and productivity and the amount of C exported by the biological pump. Presently the oceanographic community has only crude models for the amount of primary and export production and changes expected as a consequence of anthropogenic climate change. I will develop mathematical models of marine phytoplankton productivity and biomass distributions to predict effects of changing environmental conditions on primary and export production and consequences for biogeochemical cycles. My program goals are to connect phytoplankton physiological mechanisms such as acclimation to variable resources to their ecological and biogeochemical consequences, in order to predict how climate change will alter marine primary production, ecosystem dynamics and ocean carbon cycling. I will construct and test models of phytoplankton photosynthesis and growth and community composition and use databases and time-series to assess these modeling approaches, specifically taxonomic and size based traits and trait trade-offs.