U.S. Sen. Lisa Murkowski, R-Alaska, today sent a letter urging the Department of Energy to publish timely data on oil storage capacity in the United States as a warning indicator of potential shut-in oil production. The letter is addressed to Dr. Linda Capuano, Administrator of the U.S. Energy Information Administration.

“Based on my conversations with energy experts, I believe that we must prioritize the collection and analysis of data related to petroleum storage,” Murkowski wrote. “Producers will continue to produce, filling up all kinds of tanks and tankers, until capacity is reached. Available petroleum storage can serve as a gauge of the potential for shut-in production, providing us some measure of both imminence and severity.”

The request is the fourth in a series of letters Murkowski has signed, following letters to Saudi Crown Prince Mohammed bin Salman, Secretary of Commerce Wilbur Ross, and Secretary of State Mike Pompeo.