The Johnson Lab returned from a successful POWOW3 cruise having traveled more than 5000 miles in the Eastern North Pacific Ocean on a route from Hawaii to California. The goal of this research cruise, the third (and final) in the series to study Plankton in Warming Ocean Waters (POWOW), was to measure the abundance, diversity and activity of Prochlorococcus and associated bacterial and viral communities across temperature (and other environmental) gradients to understand how climate change may impact ocean ecology and biogeochemistry. To expand our understanding, we also performed temperature shift studies to experimentally assess how changes in temperature affect Prochlorococcus and other key components of the marine ecosystem. A science teacher from a local high school, three undergraduates from the Duke Marine Laboratory and a journalism student were all part of the science team that also included graduate students and our collaborators from the University of Tennessee Knoxville, University of Washington, Pacific Marine Environmental Laboratory (NOAA), and the Monterey Bay Aquarium Research Institute (MBARI). Major funding for this project was from the National Science Foundation.