Last week, a bombshell study confirmed that the oceans are warming 40 percent faster than many scientists had previously estimated. The finding partially resolved a long-running debate between climate modelers and oceanographers. By measuring the oceans more directly, scientists again came to a now-familiar conclusion: Yes, things really are as bad as we feared.
The ocean stores more than 90 percent of all excess heat energy due to the buildup of greenhouse gases in the atmosphere. From the standpoint of heat, global warming is almost entirely a story of how rapidly the oceans are changing.
Warming oceans work to melt polar ice, of course, thereby raising sea levels. But hotter oceans change how the atmosphere works, too. More heat energy in the oceans means more heat energy is available for extreme weather: Downpours of rainfall are happening more often, hurricanes are shifting in frequency and growing in intensity, freak ocean heat waves are spilling over into temperature records on land. Melting Arctic and Antarctic sea ice is also increasing wave height, which is accelerating coastal erosion — worsening the effects of sea-level rise.
The now-inevitable loss of nearly all coral reefs — home to a quarter of the ocean’s biodiversity — is the most charismatic of the impacts. The changes to the world’s oceans are shifting marine ecosystems on a grand scale, all the way down to phytoplankton, the base of the planet’s food web.
Last month, a study found that the “Great Dying,” the worst mass extinction in Earth history, was triggered by a period of global warming comparable to what’s predicted for us under business-as-usual conditions. The study asked: Could we be on a similar path as 252 million years ago, when most marine life was snuffed out after the warming seas lost most of their oxygen?
The answer, almost entirely, comes down to what we collectively decide to do in the next decade or so.
Read more at The Debate Is Over: The Oceans Are in Hot, Hot Water
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