It's not really a valley, there is slight terrain that does shelter the calving area just barely enough to make a difference. 

I'm going off memory from the Duhbya attempts to exploit ANWR 12 some years ago. I read about the proposal and sent letters to my representative, I can't remember who. Look at the track record, reckless fracking has ruined ranches in Colorado and everywhere. The Deepwater Horizon debacle and the Exxon Valdez spill indicates a bleak outlook for the caribou and the Gwich'in.

The primary issue is ANWR was supposed to be in perpetuity, Trump's rampage through every liberal sacred cow is the issue.  Global warming and the essential tact of leaving this huge carbon sink intact is part of the issue whether the LTE writer brings them up or not. 

Trashing one of the very last pristine and vital areas for gasoline is irresponsible, shortsighted, greedy, and proud. The very idea that our convenience and habits take precedence over this last wild place is obscene.