Reader Dave sends in this link on the retreating glaciers of Glacier Bay National Park. An excerpt:

As you enter Glacier Bay in Southeast Alaska you will cruise along shorelines completely covered by ice just 200 years ago.
Explorer Captain George Vancouver found Icy Strait choked with ice in 1794, and Glacier Bay was barely an indented glacier. That glacier was more than 4000 ft. thick, up to 20 miles or more wide, and extended more than 100 miles to the St.Elias Range of mountains.
By 1879 naturist John Muir found that the ice had retreated 48 miles up the bay. By 1916 the Grand Pacific Glacier headed Tarr inlet 65 miles from Glacier Bay’s mouth. Such rapid retreat is known nowhere else on earth! Scientists have documented it, hoping to learn how glacial activity relates to climate changes.

As Dave notes, this happened before man started driving around in glacier-eroding, CO2-spewing automobiles.