Armbrust, Elizabeth V.Hennon, Gwenn Michael Miller2016-03-112016-03-112016-03-112015Hennon_washington_0250E_15083.pdfhttp://hdl.handle.net/1773/35281Thesis (Ph.D.)--University of Washington, 2015Phytoplankton are responsible for approximately half the primary production on earth, fueling marine food webs and driving the cycling of carbon and inorganic nutrients in the oceans. Climate change is predicted to alter the marine environment by elevating carbon dioxide, increasing temperature, and decreasing the availability of inorganic nutrients in the surface ocean where phytoplankton dominate. To predict phytoplankton productivity and abundance in the future requires an understanding of the mechanisms of phytoplankton response to these environmental changes. Here we investigate how a model phytoplankton, Thalassiosira pseudonana, acclimates to increasing carbon dioxide through physiological and gene expression changes, and how picophytoplankton communities in the tropical Atlantic respond to variations in temperature and nutrient availability. By uncovering mechanisms of phytoplankton response to environmental variables we gain new insights into predicting how marine food webs and biogeochemical cycles may be altered by climate change.application/pdfen-UScarbon dioxide; climate change; phytoplankton; Prochlorococcus; Synechococcus; Thalassiosira psuedonanaBiological oceanographyoceanographyThesis