Each year, as humans emit billions of metric tons of CO2 into the atmosphere, nearly a third of the emissions ends up in the ocean, changing the chemical balance of the water.
And as the climate changes, the ocean is also absorbing almost all of the Earth’s extra heat, melting ice that creates sea level rise, making the water uninhabitable for marine life, and changing the planet’s weather patterns.
A new report from the IPCC, the UN panel that studies climate change, lays out exactly what’s at stake for the ocean as a result—and for humans, all of whom rely on the ocean either directly or indirectly.
“What comes out of this report is that it’s going to hit us in so many ways,” says Mark Spalding, senior marine scientist for The Nature Conservancy, one of the organizations that contributed to the report.
The litany of potential disasters from a changing ocean is horrifying: As the warming water melts ice sheets in Greenland and Antarctica, the sea level rises each year, putting hundreds of millions of people who live in low-lying coastal areas at risk of flooding.
A warmer ocean supercharges hurricanes.
Marine heatwaves can boost toxic algae and close fisheries.
As the water absorbs CO2, it becomes more acidic, posing another threat to coral reefs.
And all these impacts can exacerbate each other—coral reefs, for example, “play the role of a sea wall,” says Spalding. “They sit offshore like a barrier and they break waves before the waves get to land.” As storms get stronger, this natural protection is being lost at the same time.
Source: Latest IPCC report: The ocean is in more danger than we thought