The changes to Earth's energy system have major ramifications for the planet's future climate and humanity's understanding of climate change.
The findings undercut a key argument used by people who do not believe human activity is responsible for the bulk of climate change to explain trends in global warming, demonstrating that the planet's energy imbalance cannot be explained just by Earth's own natural variations.
The research also offers important insights into how greenhouse gas emissions and other consequences of human-caused climate change are upsetting the planet's equilibrium and driving global warming, sea-level rise and extreme weather events.
"With more and more changes to the planet, we've created this imbalance where we have surplus energy in the system," said Shiv Priyam Raghuraman, a graduate student in atmospheric and oceanic sciences at Princeton and lead author of the study.
"There isn't this equilibrium between energy coming in from the sun and energy going out," Raghuraman said.
They then used a series of climate models to simulate the effects on Earth's energy system if human-caused climate change was taken out of the equation.
"It was almost impossible â€” a less than 1 percent probability â€” that such a large increase in the imbalance was from Earth's own oscillations and variations," Raghuraman said.