Tasman Glacier dead ice wilderness

Moraine "wall" above the lake -- the debris is all resting on dead ice, and is very dangerous indeed.  Material is constantly sliding down into the lake.

The sharp crest of the main moraine ridge near the village.  Many people walk along the crest of the ridge -- not a good idea.  Note the dead-ice wilderness filling the whole of the glacier tough.

Scary!  Too many paths, too close to the edge.....

Annotated photo showing the moraine "wall" and the dead-ice chaos below.

Dead-ice terrain, in the Tasman Glacier valley.  Along the edge of the ice-dammed lake you can see that the terrain is all ice-cored.

Much as I love glaciers, I am genuinely scared of terrain like this. It's one of the most obvious signs of global warming.  Glaciers in all the high mountain regions of the world are melting catastrophocally, replacing areas of clean firm ice with this sort of landscape.  The Himalayan glaciers  are being transformed at an unprecedented rate.

Here is some Google satellite imagery:

Here we see the dead-ice wilderness from above.  The valley is between 2 and 3 km wide.  The meltwater lake is at the base of the photo, and the clean glacier snout is off the top of the photo.  The dead ice area covers about 24 sq km.

Close-up of part of the moraine surface.  Note the temporary meltwater lakes and the crescentic fractures where collapses have occurred.

The junction between the lateral moraine and the dead ice zone on the valley floor.  The track to the Ball hut runs on the outside of the moraine ridge, but people stop and clamber up onto the ridge crest far too frequently, just to get a better view.  Not a good idea. For the authorities, a tourist management nightmare.......

Remember, dear readers, that the Tasman Glacier surface was -- before it started its catastrophic melting -- located at the TOP of the lateral moraine ridge. Measurements suggest that the glacier surface has dropped by around 250m since 1880.  Even given that New Zealand glaciers are very dynamic, with rapid ice turnover, that is a phenomenal rate of glacier wastage.