Estimated heat entering the ocean since midnight UTC, in exajoules. One exajoule is roughly what the United Kingdom uses in energy across two months.

Ocean heat content is assessed from float and float-derived data over months, not continuously. The per-second figure conveys scale; for a measured value, prefer the readings on the observed page.

Nobody counts this as it happens. EarthNow takes a published figure for the whole day, divides it by the 86,400 seconds in a day, and multiplies by the seconds elapsed since midnight UTC. So the value climbs smoothly and is the right order of magnitude — but the smoothness is arithmetic, not observation. Nothing happening in the world is being watched in real time.

value = daily total ÷ 86,400 × seconds since 00:00 UTC

A consequence worth knowing: the counter resets at midnight UTC, not at your midnight. And because every signal advances at a constant rate, this page cannot tell you whether today is unusual. For that you need a measurement.

Ocean heat content rises by roughly 15 zettajoules (15,000 EJ) a year.

Daily total

41 EJ

Published by

NOAA NCEI (2024)

The figure is theirs; the running total is ours. Cite them for the number, and EarthNow for what it looks like as it accumulates.

• The imbalance between sunlight arriving and heat escaping, which greenhouse gases control
• How deep the heat mixes, which decides whether it returns in a decade or a century
• Ocean circulation, which moves heat away from where it entered