Earth's Energy Imbalance
The Earth system is accumulating heat at an increasing rate
Explanation
Earth's energy imbalance (EEI) is the difference between the amount of energy the Earth absorbs from the Sun and the amount of energy it radiates back into space. Increasing concentrations of greenhouse gases reduce the rate at which energy leaves the Earth system, trapping energy in the Earth System. The CERES satellite measures changes in the EEI directly. EEI can also be estimated from changes in ocean heat because more than 90% of the trapped energy goes into the ocean.
Methodology
The Earth's Energy Imbalance (EEI) can be measured in two ways:
- The Earth heat inventory (1960–present). This method combines separate estimates of heat stored in the ocean, land and atmosphere, as well as the energy needed to melt ice. This hybrid approach integrates the Global Climate Observing System (satellite and in situ) data, reanalyses and climate models. A preliminary estimate of the inventory can be made using the observed ocean heat content (as is done here) since the ocean stores most of the excess heat accumulated in the Earth system.
- Direct satellite measurements (2000–present) of the incoming and outgoing radiation at the top of the atmosphere
The values shown here are evaluated over a 15 year period, focusing on the longer-term changes that can be estimated consistently from the two methods.
Values from the remote-sensing method are anchored to the data from Minière et al. (2023). This means that the absolute values of the EEI measured in the two complementary ways are not independent, but change in the values are.