Speaking Wednesday on Boston Public Radio, climate activist and writer Bill McKibben lauded President Joe Biden’s flurry of executive actions targeting climate change, calling the administration’s efforts to priorite environmental action “extraordinarily interesting."

Among other moves made in the two weeks since he assumed office, Biden has established a National Climate Task Force, paused new leasing of federal lands and waters for fossil fuel production, placed an emphasis on mitigating the national security risks presented by worsening natural disasters and re-joined the Paris Climate Accord, bringing the U.S. back in step with 189 nations around the globe.

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"Some of this stuff is easy and obvious," McKibben said. "Rejoining the Paris Climate Accords doesn’t take very much insight. But other things are tough calls … bringing the 10-year battle over the Keystone Pipeline to an end, saying ‘we’re not going to do this anymore' — that was a big deal. So were a lot of the other things that they’re talking about. Not all of them quite as visible, but all of them, so far, [are] powerful.”

The 350.org founder said growing public concern around global warming, paired with cheapening renewable energies and an "effective educational job” from Mother Nature have made it more feasible that the Biden administration’s efforts will last after his presidency.

“The zeitgeist has begun to shift — our sense of what’s normal, and natural, and obvious,” he said. "And that won’t, I think, shift back ... any more than, say, when the zeitgeist shifted about gay marriage."

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The looming climate crisis, however, remains a significant threat for much of humanity. A 2020 report from the United National Environment Programme found that nations are continuing to emit fossil fuels at levels that would warm the planet a whole 3° Celsius, all but ensuring the catastrophic consequences spurred by worsening natural disasters, rising sea-levels and a heightened capacity for the spread of infectious diseases.

"The problem here is only that time is incredibly short if we’re ever going to catch up with the physics of climate change, because we’ve wasted so much time already," McKibben said, stressing that Biden will have to accelerate efforts to wean the U.S. off of fossil fuels.

Bill McKibben is a contributing writer for The New Yorker, a founder of the advocacy group 350.org and the Schumann Distinguished Scholar in environmental studies at Middlebury College. He also writes The Climate Crisis, The New Yorker’s environmental newsletter. His latest book is “Falter: Has The Human Game Begun To Play Itself Out?”