Danny Westneat:

Eight years until "Glacier National Park" is just "National Park." The ice had been the lure to get the family to go see the great glaciers before they're gone. But I misjudged how far gone they already are. As did the scientists.

Just say it like it is:

"Global warming is melting the glaciers that give Glacier National Park its name," it says. "By 2030, they all could be gone."
This is about our world, which is not the earth (our planet is here to stay), but a moment in earth's history. If this moment goes, we go with it. What ever faith certain powerful people have in human adaptability, know that human culture will find its limit when this moment goes.