Jan 16, 2024 - Energy & Environment

2023 shattered records for ocean heat content

Energy in Earth's oceans at 0-2,000 meters
Data: John Abraham, University of St. Thomas; Chart: Axios Visuals

Last year broke a record for the most heat content present in the upper 2,000 meters (6,562 feet) of the oceans.

Why it matters: The oceans absorb about 90% of the extra heat in the Earth system trapped by greenhouse gases, making the metric a striking indicator of human-caused global warming.

By the numbers: The five highest values of annual ocean heat content have come in the past five years, according to NOAA.

The big picture: "If you want to know how fast and how far global warming is going to go, the answer is in the oceans," study coauthor John Abraham told Axios.

  • Sea surface temperatures were also off the charts in 2023, which helped drive extreme weather on land, too. However, surface temperatures are only a small part of the heating that took place in deeper waters, Abraham said.
  • Parts of every ocean had record warm sea surface temperatures, particularly in the North Atlantic and equatorial tropical Pacific.

The bottom line: According to the temperature tracking group Berkeley Earth, "[n]o places on Earth experienced a record or near-record cold annual average" in 2023.

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