Ocean warming accelerates, driven by energy imbalance and reduced reflectivity

Earth’s oceans have warmed at an unprecedented rate over the past 40 years due to greenhouse gas emissions and diminished atmospheric reflectivity, with consequences for coral reefs, weather and marine ecosystems.

Sachi Kitajima Mulkey reports for Grist.


In short:

  • A study found the rate of ocean warming has quadrupled in four decades, tied to Earth's energy imbalance caused by rising greenhouse gases and reduced reflectivity.
  • Diminished marine clouds, due to reduced sulfur pollution, have increased ocean heat absorption, compounding the warming effect.
  • Record-high sea surface temperatures have triggered mass coral bleaching, stronger hurricanes and shifting weather patterns.

Key quote:

“The oceans really set the pace for global warming for the Earth as a whole.”

— Christopher Merchant, University of Reading professor of ocean and earth observation

Why this matters:

Oceans absorb 90% of excess heat from human activity, fueling climate impacts like coral die-offs, extreme storms and weather shifts. Rapid warming highlights the urgency of reducing emissions and adapting to accelerating climate impacts.

Related EHN coverage: Surprise! Unexpected ocean heat waves are becoming the norm

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