This post was originally published on Legal Planet. Reprinted with permission.

A recent Ninth Circuit ruling overturned approval of offshore drilling in the Arctic. The ruling may directly impact the Trump administration's plans for oil leasing in the Arctic National Wildlife Refuge (ANWR). By requiring agencies to consider emissions when fossil fuels are ultimately burned, the Court of Appeals' decision may also change the way agencies consider other fossil fuel projects, such as gas pipelines.

In Center for Biological Diversity v. Bernhardt, environmental groups challenged the Interior Department's approval of an offshore drilling and production facility on the north coast of Alaska. In its environmental impact statement, the agency refused to consider the effects of the project on carbon emissions outside the United States.

On its face, as the court was quick to point out, the agency's position makes no sense. It's like assuming that if you pour water in one end of the bathtub, it won't rise on the other end. There's a world market for oil, so increased supply anywhere means that prices go down and world demand goes up. The Interior Department also said that the effect on emissions was too uncertain to quantify, but the court …