Recent advances in sequencing technology have highlighted the extreme diversity of marine microbes and provided insights into their evolution (1–3). It remains unclear, however, how ocean microbial communities are responding to ongoing climate change. This is because pinpointing change with statistical rigor requires long-term studies that sample the same location or water mass repeatedly. On page 326 of this issue, Hunter-Cevera et al. (4) present a highly resolved long-term study of a widespread cyanobacterial phytoplankton group, Synechococcus. They show that the timing of the annual spring Synechococcus bloom has shifted in association with ocean warming.
Authors: Alexandra Z. Worden, Susanne Wilken