Without Climate Action, Massive Marine Die-off at Stake

Without Climate Action, Massive Marine Die-off at Stake

According to a recent study, if global temperatures continue to rise, marine ecosystems will likely experience a mass extinction event “on par with past great extinctions.” And if current emissions aren’t curbed, “a third of all marine animals could vanish within 300 years,” the Washington Post reports.

Healthy ecosystems are being destroyed, largely caused by carbon emissions that cause ocean temperatures to rise. Increased temperatures deplete the waters of oxygen and make them more acidic -- effects that will increase existing extinction rates. Most marine animals need at least 50% of their habitats preserved to survive.

BBC: Past seven years hottest on record, EU satellite data shows, January 10, 2022.

The Climate Project India: Ocean warming, December 24, 2021.

Simon Clark: Why the sixth mass extinction is here. Now., March 4, 2022.

Why this Matters

The seas provide habitats for millions of marine species. They are also vital to humans and the economy, providing food for 3 billion people and in total the blue economy provides jobs for over 350 million people worldwide. Still, they severely lack protection, with only about 1% of their total surfaces designated as “protected,” and between 10% and 15% of marine species already face extinction due to anthropogenic effects such as pollution and overfishing.

As critical carbon sinks, oceans absorb a third of all carbon emissions and 90% of all anthropogenic heat while helping to regulate the climate. Earth’s waters hold up to 15 times more CO2 than land ecosystems while producing between 50 and 80% of the planet’s oxygen.

This study underlines that there’s no stopping the damage already done by global warming and that immediate action is necessary to prevent matters from getting worse. According to coverage in the Guardian, current climate pledges are likely to result in “around 4% of the roughly two million species in the oceans [being] wiped out.”

DW: Higher temperatures and plastic pollution threaten oceans, February 11, 2022.

Natural World Facts: The Marine Carbon Cycle Explained, November 16, 2021.

Some Hope

With immediate action, it’s still possible to prevent a worst-case marine die-off event. Curbing fossil fuel use and restoring damaged ecosystems could reduce projected extinctions by 70%. The study is yet another wake-up call that more climate legislation and swift reductions in greenhouse gas emissions are needed.

“We found that the future extinction magnitude depends on the eventual amount of CO2 we emit moving forward,” said Justin Penn, one of the study’s authors. “It’s up to us to decide,” he added.

CBS: Huge carbon emissions cuts needed, UN climate report finds, April 4, 2022.

IEA: A 10-Point Plan to Cut Oil Use, March 18, 2022.