Arecent mountaineering trip found me and two climbing partners camping alongside a beautiful glacial lake in North Cascades National Park.

Purple flowers swayed in the cool breeze coming down from the glacier above us. No less than five wispy waterfalls flowed down a rock wall behind our camp — the melting runoff from a smaller glacier up above.

The scene was idyllic, but it also betrayed a sinister reality. The place where we were camping used to be all glacier. The lake beside us used to be solid ice. Now, like most glaciers globally, the glacier is in rapid retreat.