Our oceans are the world’s biggest carbon sink. They’ve absorbed about one-third of all human-induced carbon dioxide emissions, and play a crucial role in stabilizing the planet’s climate. That’s thanks in no small part to tiny organisms at the base of the marine food chain called phytoplankton, which gobble up atmospheric carbon dioxide and release oxygen in its place.

But according to a new study, marine heatwaves are hampering the ocean’s ability to keep this CO-2 locked up below the surface.

Here & Now‘s Rob Schmitz speaks with Grist senior staff writer Matt Simon.

This article was originally published on WBUR.org.

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