Global energy-related carbon dioxide emissions rose by six percent in 2021 to a record 36.3 billion tonnes, their highest ever level, the International Energy Agency said Tuesday.
"The increase in global CO2 emissions of over 2 billion tonnes was the largest in history in absolute terms, more than offsetting the previous year's pandemic-induced decline," it said.
It pointed to the widespread use of coal to power growth as the world economy rebounded from the Covid crisis.
"The recovery of energy demand in 2021 was compounded by adverse weather and energy market conditions -- notably the spikes in natural gas prices -- which led to more coal being burned despite renewable power generation registering its largest ever growth," it said.
The IEA said the rebound of global CO2 emissions above pre-pandemic levels was largely driven by China, where they increased by 750 million tonnes between 2019 and 2021.
"China was the only major economy to experience economic growth in both 2020 and 2021," it said.
"The emissions increases in those two years in China more than offset the aggregate decline in the rest of the world over the same period."
In 2021 alone, China's CO2 emissions rose above 11.9 billion tonnes, accounting for 33 percent of the global total.