Why Zettajoules Matter for Ocean Warming and Climate Change

Why Zettajoules Matter

Most people have heard of joules as a unit of energy, but zettajoules are increasingly being used in discussions about climate change and warming oceans. A zettajoule equals a billion trillion joules, or one followed by 21 zeros.

Scientists have been using zettajoules to calculate Earth’s energy imbalance. The higher that number rises, the worse the imbalance becomes, because it means the planet is absorbing more energy than it is releasing back into space.

Oceans And Energy Imbalance

Much of that excess energy is absorbed by the oceans, making ocean warming a central part of the climate story. Warmer oceans can have major effects on weather, including stronger hurricanes and increased flooding from rainstorms.

The article points to 2025 as a stark example of how serious the problem has become. Rising ocean heat and a growing energy imbalance are presented as immediate concerns rather than distant ones.

Records In 2025

Between 2005 and 2025, Earth’s energy imbalance increased by 11 zettajoules per year on average. That amount is about 18 times total human energy usage.

In 2025 alone, however, the energy imbalance increased by 23 zettajoules, or about 39 times total human energy usage. The article says this growing accumulation of energy is tied to burning fossil fuels and greenhouse gases, underscoring that the problem is active and needs to be addressed.