Responding to the CO2 Coalition's "Fact #32" on Glacier Bay Melting

CO2 Coalition's "Fact #32" tries to make a point from Glacier Bay's glacial history. They feel like since glaciers have retreated in  Glacier Bay since the late 1700s, that this is some how an argument that humans aren't causing the planet to warm. Here's a map with annotations from the CO2 Coalition.

The declarations of what is "natural melting" and "man-made melting" are simply the opinions of CO2 Coalition. The map as published by the USGS looks like this.


The figure's description describes how the southern terminus positions have changed since 1794, but interestingly I can find nothing this description or associated text any reference to the attribution of when the retreat was "natural" and when it transitioned to "man-made." All that appears to be made up by the CO2 Coalition. Here's the description:
Location map of Glacier Bay National Park showing terminus positions and dates of retreat of the Little Ice Age glacier that completely filled the bay somewhat more than 200 yrs ago. The 1794 terminous line near the mouth of the bay is where Capt. George Vancouver and crew observed the massive glacier face during their hunt for the Northwest Passage. The 1879 glacier terminous position was mapped by John Muir during his first of several visits to Glacier Bay. Trapezoid outlines the Whidbey Passage study area. Modified from Seramur et al. (1996).
If there is no attribution on the USGS website, maybe it's in Seramur et al 1996? So I looked it up. The paper is fascinating, but there's no attribution in that paper either. So where is the glacial retreat from Glacier Bay cited as "proof positive of man-made warming?" CO2 Coalition forgot to supply that. Actual evidence shows that many mountain glaciers advanced into the height of the Little Ice Age, and then they began to retreat. CO2 concentrations began to increase due to human activity around 1750, and emission rates have accelerated following 1850 or so, with exponential growth in the 20th century. Temperatures have increased at rates consistent with the increase in CO2, regardless of the specifics of individual glaciers at locations cherry-picked by the CO2 Coalition.


References:

[1] Seramur, Keith C., Powell, R.D., Carlson, P.R., 1996. Evaluation of conditions along the grounding line of temperate marine glaciers: an example from Muir Inlet, Glacier Bay, Alaska. Marine Geology 140, 307-327. https://doi.org/10.1016/S0025-3227(97)00026-1

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