Millennial-scale plankton regime shifts in the subtropical North Pacific Ocean

See allHide authors and affiliations

Science  26 Nov 2015:
DOI: 10.1126/science.aaa9942

You are currently viewing the abstract.

View Full Text


Climate change is predicted to alter marine phytoplankton communities and affect productivity, biogeochemistry, and the efficacy of the biological pump. We reconstructed high-resolution records of changing plankton community composition in the North Pacific Ocean over the past millennium. Amino acid–specific δ13C records preserved in long-lived deep-sea corals revealed three major plankton regimes corresponding to northern hemisphere climate periods. Non-N2 fixing cyanobacteria dominated during the Medieval Climate Anomaly (950-1250C.E.) before giving way to a new regime where eukaryotic microalgae contributed nearly half of export production during the Little Ice Age (~1400-1850C.E.). The third regime, unprecedented in the last millennium, began in the industrial era and is supported by increasing N2-fixing cyanobacterial production. This picoplankton community shift may provide a negative feedback to rising atmospheric CO2.

View Full Text