Arctic air is blanketing large swaths of the country, including North Dakota, where hundreds of protesters are still camped out near the Standing Rock Sioux reservation. Earlier this month, the Army Corps of Engineers announced plans to temporarily stop construction on the Dakota Access Pipeline. The Standing Rock Sioux took issue with the pipeline’s originally planned route, which would have run underneath a lake near the reservation. President-elect Donald Trump has said he’ll try to overturn the decision.