Joe Biden becomes the nation’s 46th president. He immediately halts the Keystone XL Pipeline, rejoins the Paris climate accord, stops oil drilling preparations in the Arctic National Wildlife Refuge, and freezes all new and pending Trump regulations, including a rollback of auto fuel-efficiency standards. 

More than 400,000 Americans are dead of COVID-19. Also, more than 400,000 clean energy jobs have been lost because of the pandemic. 

So many people are dying of COVID-19 in Los Angeles County that regional air-quality regulators have lifted pollution limits on local crematoria.

On his way out of Washington, former president Donald Trump grants 10-year grazing permits to Oregon ranchers Dwight and Steven Hammond, who lost their previous permit after being convicted of illegally burning public rangeland. That denial led to the 2016 occupation of the Malheur National Wildlife Refuge by anti-government militants.

A court strikes down Trump’s Affordable Clean Energy Rule, Trump’s proposed replacement of Obama’s Clean Power Plan, ruling that it fails to protect the environment and public health.

North America badly underestimates the amount of atmosphere-warming methane leaking from abandoned oil and gas wells. US estimates are off by 20 percent, Canada’s by 150 percent.

California utilities are cutting off power to customers to avoid sparking wildfires—in the middle of January.

Ocean temperatures in 2020 reached a record high.

An all-Nepali team of 10 Sherpas is the first to summit K2 in winter, the last of the world’s 14 highest peaks to be climbed in the off-season. The team paused just below the peak so they could step up to the summit together. 

A lump of agate discovered in the Brazilian state of Rio Grande do Sul bears a strong resemblance to Sesame Street’s Cookie Monster.

After a 500-year absence, wild lynx may be reintroduced to Scotland’s Highlands.