climate change and all that rarely features in dark tourism (DT), probably because DT is predominantly about dark pasts, not about the future. Moreover, climate change symptoms already in evidence rarely produce visitable concrete tourist sites. But there are a few exceptions, most notably retreating glaciers.
Most glaciers in the world are shrinking due to global warming. And occasionally the shrinkage is marked by signs on tourist walking routes. Here’s an example I spotted in Norway en route to the Briksdalsbreen