> It's hard to appreciate the scale of these places unless you have visited them.

I think what’s especially hard to grasp from pictures is not just the areal loss, but the massive amount of volume that has vanished. For example, the Aletsch glacier, (at a length of 23 km, the biggest one in the Alps) has lost more than 100m of thickness in only 150 years. If you stand on its surface as it is today, it’s impressive to realise what a sheer amount of ice there used to be above your head and around you just a few decades ago.