Ocean temperatures helped make 2023 the hottest year ever recorded

A multi-national team of scientists (China, U.S., New Zealand, Italy, and France) analyzes the temperature of the Earth annually. These scientists have found a fever that increases every year: For the past decade, each year has been hotter than the prior year in the ocean, and there are other changes in the ocean that also matter.

The ocean is an important part of the Earth’s climate system—it covers 70% of the planet and absorbs about 90% of the heat from global warming. The ocean helps control the atmosphere—a warmer ocean leads to a warmer and moister atmosphere with wilder weather. The ocean also controls how fast the Earth’s climate changes. To understand what has happened or what will happen to the planet, answers can be found in the ocean.

The data were obtained from two research teams: the Institute of Atmospheric Physics (IAP) at the Chinese Academy of Sciences (CAS) and the National Centers for Environmental Information of the National Oceanic and Atmospheric Administration (NOAA). Based on temperature measurements analyzed by the IAP, the world ocean heated by 15 zettajoules relative to 2022. According to NOAA, the heating was smaller, 9 zettajoules. Both groups reported another year of warming, but their magnitudes differed, as addressed below.