President Trump grants ethics waivers to 17 senior officials, absolving them of ethical guidelines and permitting former lobbyists to work on the same issues that corporations once paid them to influence. Among these is Mike Catanzaro, who formerly lobbied for the American Chemistry Council and the American Fuel & Petrochemical Manufacturers, and who will now craft administration policy on the Clean Power Plan and other energy matters.

EPA administrator Scott Pruitt says he will delay implementation of 2015 smog standards for a year. 

Pruitt claims that 50,000 coal jobs have been created under the Trump administration. The correct figure is 1,000 jobs. 

Following President Trump’s withdrawal of the United States from the Paris climate accord, reporters try to determine whether Trump still believes that climate change is a hoax. No one will say.

David Rank, the U.S. chargé d’affaires in Beijing, resigns over Trump’s withdrawal from the Paris Agreement.

2016 had the second-biggest jump in atmospheric carbon dioxide levels on record—nearly double the previous pace.

Prince is revealed to have been a secret patron of clean energy—before his death, he anonymously funded a tech incubator for solar companies.

Trump proposes that his border wall be 50 feet high and outfitted with solar panels. 

U.S. solar companies resume selling rooftop solar arrays in Nevada after the state reinstates “net metering,” a pro-solar policy that its public utility commission had scrapped in 2015. 

In South Africa, two elderly circus lions that had been rescued from South America and transported to a wildlife refuge are killed by poachers.

The Trump administration moves to allow oil companies to harm marine mammals while conducting seismic testing for oil off the Atlantic coast.

Interior Secretary Ryan Zinke signs an order aimed at increasing oil production in arctic Alaska. 

Climber Alex Honnold free solos—i.e., climbs alone without ropes or protection of any kind—Yosemite National Park’s El Capitan.

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