• DOI:10.1126/science.aay8380
• Corpus ID: 220433818

Changes in phytoplankton concentration now drive increased Arctic Ocean primary production

@article{Lewis2020ChangesIP,
  title={Changes in phytoplankton concentration now drive increased Arctic Ocean primary production},
  author={Kate M. Lewis and Gert L. van Dijken and Kevin R. Arrigo},
  journal={Science},
  year={2020},
  volume={369},
  pages={198 - 202}
}

• K. Lewis, G. V. van Dijken, K. Arrigo
• Published 10 July 2020
• Environmental Science
• Science

Food for thought Phytoplankton abundances in the Arctic Ocean have been increasing over recent decades as the region has warmed and sea ice has disappeared. The presumptive causes of this increase were expanding open water area and a longer growing season—at least until now. Lewis et al. show that although these factors may have driven the productivity trends before, over the past decade, phytoplankton primary production rose by more than half because of increased phytoplankton concentrations (see the Perspective by Babin). This finding means that there has been an influx of new nutrients into the region, suggesting that the Arctic Ocean could become more productive and export additional carbon in the future. Science, this issue p. 198; see also p. 137 Increases in Arctic Ocean primary production are now mainly due to a rise in phytoplankton concentration. Historically, sea ice loss in the Arctic Ocean has promoted increased phytoplankton primary production because of the greater open water area and a longer growing season. However, debate remains about whether primary production will continue to rise should sea ice decline further. Using an ocean color algorithm parameterized for the Arctic Ocean, we show that primary production increased by 57% between 1998 and 2018. Surprisingly, whereas increases were due to widespread sea ice loss during the first decade, the subsequent rise in primary production was driven primarily by increased phytoplankton biomass, which was likely sustained by an influx of new nutrients. This suggests a future Arctic Ocean that can support higher trophic-level production and additional carbon export.