Ocean heat content tracker

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Interpretation

Heat content of the world ocean, the Atlantic (which in NOAA's data includes the Arctic Ocean), the Pacific and the northern-hemisphere part of each, and the Indian Ocean, from the surface to 2000 m depth (published from 2005) and to 700 m depth (from 1955), as anomalies relative to NOAA's 1955–2006 climatology, in zettajoules (1 ZJ = 10²¹ joules). 3-month values cover Jan–Mar, Apr–Jun, Jul–Sep and Oct–Dec; the shaded band is ±2 standard errors. Measurements were sparse before the Argo float network reached global coverage in the mid-2000s, so early values are less certain. Heating rates are linear trends converted to watts per square meter of Earth's whole surface (510 million km²), so they can be compared with the energy imbalance page. Humanity's energy use: about 600 EJ (0.6 ZJ) per year (Energy Institute, Statistical Review of World Energy 2026). Data: NOAA National Centers for Environmental Information, Global Ocean Heat and Salt Content (ncei.noaa.gov); Levitus et al. (2012).