GFDL - Geophysical Fluid Dynamics Laboratory

Anthropogenic climate change drives shift and shuffle in North Atlantic phytoplankton communities

February 22nd, 2016

Andrew D. Barton, Andrew J. Irwin, Zoe V. Finkel, Charles A. Stock. Proceedings of the National Academy of Sciences. DOI:10.1073/pnas.1519080113

Summary

This study estimates the impact of projected anthropogenic climate change over the next century on marine phytoplankton communities, and increases our understanding of the environmental drivers of ecological change. The change in biogeography for North Atlantic phytoplankton taxa in response to anthropogenic climate change is quantified, and the primary physical drivers of the projected changes are diagnosed. These findings indicate that over the course of the next century, climate change may significantly modify phytoplankton assemblages throughout the North Atlantic, and may shift individual species ranges considerably, on a magnitude of the exclusive economic zones for the marine territory of many countries.

The study is the first of its kind to examine the climate responses of a large number of phytoplankton species to a broad range of environmental drivers. The authors integrated statistical modeling tools and climate model output, leveraging extensive observations from the North Atlantic region.

Employing the “bioclimate envelope” approach, the authors quantified the realized ecological niche for each species from historical observations, and used this species distribution model (SDM) to map and compare species biogeographies in modeled historical (1951-2000) and projected future (2051-2100) ocean conditions. SDMs were constructed by pairing a half-century of Continuous Plankton Recorder (CPR) species observations with co-located climatologies for 7 observed environmental predictor variables generally found to impact phytoplankton physiology and abundance.

North Atlantic phytoplankton communities support extensive economically important fisheries. As such, their variability and response to climate change are important to understand and assess. This study may help inform climate mitigation and adaptation choices.

The projected change in core biogeographic range between historical (1951-2000) and future conditions (2051-2100) for 87 phytoplankton species is indicated in the left panel; red arrows are taxa moving north, blue arrows are taxa moving south. The range shifts produce changes in community composition and species richness. The right panel indicates the projected change in species richness over the coming century.
The projected change in core biogeographic range between historical (1951-2000) and future conditions (2051-2100) for 87 phytoplankton species is indicated in the left panel; red arrows are taxa moving north, blue arrows are taxa moving south. The range shifts produce changes in community composition and species richness. The right panel indicates the projected change in species richness over the coming century.