Once again, the world’s oceans are setting records that are annually broken. In a paper published on Monday in the journal Advances in Atmospheric Sciences, researchers found that 2021 was not only the hottest year on record for humans, but also for ocean temperatures. When it comes to tracking the heat of the ocean, scientists measure that in joules. Joules track the energy taken to move 1 kilogram of mass at 1 meter per second. One joule is the equivalent of one-3,600th of a watt hour, which is not a lot of power generated in a small amount of space. Being that even the smallest ocean, the Arctic Ocean, has a surface area of more than 14 million kilometers, scientists measure ocean heat in zettajoules, with zetta referring to 1 sextillion. 

One of those researchers who co-authored the 2021 paper and past findings, John Abraham, offered a startling example of just how much energy and heat the ocean is absorbing in The Guardian last year. “The amount of heat we are putting into the oceans is equivalent to about five Hiroshima atom bombs of energy every second,” Abraham noted. That energy certainly adds up and has led to the top 2,000 meters of all oceans absorbing 14 more zettajoules in 2021 than in the prior year. Researchers noted that the uptick has been relatively consistent since records began being kept in the 1950s, but has only grown more intense over the past half dozen years. Hotter oceans are one of the main indicators of climate change and can have devastating effects on ocean dwellers and land dwellers alike. The rise in temperatures are responsible for coral bleaching, coastal erosion, the elimination of wetlands, and other major consequences like more deadly weather events.