Aug 31, 2022 - Energy & Environment

Ocean heat reached all-time high in 2021, report finds

Illustration for story about research into ocean warming

Illustration: Sarah Grillo/Axios

Ocean heat content, global sea levels and greenhouse gas concentrations all reached record highs in 2021, according to the State of the Climate report published Wednesday.

The big picture: The annual report showcases compelling scientific evidence that climate change has global impacts and shows no sign of slowing, said Rick Spinrad of the National Oceanic and Atmospheric Administration, which led the study.

Our thought bubble: The ocean heat content findings are a sign of a planet that is absorbing far more heat than it is releasing back into space.

  • The oceans are absorbing the vast majority of the extra heat trapped by greenhouse gases, which were also at the highest level on record last year.

Why it matters: Ocean warming is increasingly tied to extreme weather and climate events.

Worth noting: the global average sea level rose to a record-high for the 10th consecutive year.

  • The global average sea level was about 3.8 inches higher in 2021 than the 1993 average, when the satellite measurement record began.

1 big thing: Earth's warming trend is continuing, with 2021 among the six warmest years since records began in the mid-to-late 1800s, the report found.

  • The past seven years (2015–2021) were the seven warmest years on record.

The bottom line: "With many communities hit with 1,000-year floods, exceptional drought and historic heat this year, it shows that the climate crisis is not a future threat but something we must address today as we work to build a Climate-Ready Nation — and world — that is resilient to climate-driven extremes," Spinrad said in a statement.

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