New data shows global energy-related emissions were actually 2% higher in December 2020 than they were in the same month a year earlier.
Global average temperatures last year were tied for the hottest on record, capping what was also the planet's hottest decade ever recorded, according to new data analysis released Friday.
At least 15 other countries have already made similar commitments, including Germany, France and Norway.
Twenty-three states have sued to stop the Trump administration from revoking California's authority to set emission standards for cars and trucks.