Gazing up at mountains from their valleys down below, it's hard, if not impossible, to detect any change on the top of the mountains. But change is ongoing, especially in recent history as the climate continues to warm.

From Tacoma or Seattle in Washington state, the snowy summit of Mount Rainier National Park appears unchanged from how it's always looked. Snowy. But is that truly the case? What would you think if someone told you the top of the summit no longer is 14,410 feet high, that the high point of the park has actually shrunk?

Our guests today are Eric Gilbertson, a mechanical engineer and mountaineer from Seattle University, and Scott Hotaling, a watershed sciences professor from Utah State University, who have measured the thickness of the ice cap on the summit of Mount Rainier. What they have to say may surprise you.