A version of this post first appeared in The Hill on December 22, 2016.

President Obama has done more than any previous president to lead the United States and the world in the battle against climate change. We owe him our enduring gratitude for this leadership.

On Tuesday, President Obama did even more: He withdrew most of the Arctic Ocean and important parts of the Atlantic Ocean from expanded offshore drilling—for good. Specifically, the president designated 115 million acres in the Arctic’s Beaufort and Chukchi seas and 31 undersea canyons in the Atlantic Ocean off limits to drilling, accompanied by related action in Canadian waters by Prime Minister Justin Trudeau.

Before the November 8th election, I joined a group of leaders of environmental organizations to send President Obama a letter asking him to take action to permanently protect these oceans. Our request was supported by many members of Congress, prominent members of the scientific community and hundreds of thousands of people across the country. Indeed, a recent poll shows that nearly 60 percent of Americans support permanent protection of the Arctic and Atlantic oceans from oil and gas drilling. The results of the election only heightened the urgency of these calls.

Permanent protection of the Arctic and Atlantic oceans from future oil and gas lease sales makes enormous sense. Offshore oil drilling directly harms sea life and risks devastating oil spills that history shows cannot be contained or cleaned up. Because of these risks, Earthjustice has worked for a decade to keep unwise drilling out of the irreplaceable, pristine and sensitive waters of the Arctic Ocean, which are already under dire threat from climate change. The president’s action on Tuesday will substantially advance protection from oil spills and other impacts for wildlife in these regions, including species already threatened by accelerated warming in the Arctic Ocean, such as polar bears, seals and walruses.

Tuesday’s action also helps the global community gird against climate change. Offshore oil from undeveloped frontiers like the Arctic and Atlantic has no legitimate place in our energy future. In order to meet key global carbon emissions goals—and to keep global warming below 2 degrees Celsius—scientists around the world agree that much of the oil still in the ground and under the ocean floor will need to remain there, for good. 

Our letter to the president stated: “The current lack of infrastructure for drilling the oceans’ outer continental shelves means oil production—if feasible at all—would be decades away, arriving too late to fuel America’s transition to a low-carbon economy. It would also require massive public and private investments that should instead go into clean energy.”

As Earthjustice has advocated for years, today’s energy investments should focus our resources on developing clean, renewable sources of power, not opening undeveloped areas to dangerous and expensive offshore drilling. Sinking investments into future fossil fuel extraction would only hinder the necessary transition to clean energy.

By permanently protecting much of the Arctic Ocean and important areas in the Atlantic from oil drilling, the president took another important step toward averting the worst effects of climate change. President Obama has been a hero in the fight against climate change. History shows that actions like this one, under the Outer Continental Shelf Lands Act, stand the test of time; no president has ever reversed a permanent withdrawal from drilling. With an incoming presidential administration hostile to the scientific consensus on the climate dangers we face, this final move by President Obama could not be more important.