An unusual Antarctic feature
An ice tongue is an unusual glacial feature that is created when an ice stream that is travelling faster than the surrounding ice pushes out to sea ahead of the glacier’s edge. It isn’t something that happens everywhere but it’s not uncommon either-Antarctica has 19 ice tongues.
However, for an ice tongue to remain intact it requires special conditions, like a protected harbour that minimises the effects of tide and iceberg impacts. Luckily these conditions can be found at McMurdo Sound.
The Erebus Ice Tongue is a slender peninsula that protrudes 11 kilometers from the Antarctic coastline out into the sea ice. The ice tongue produces icebergs when parts of it break away but since the Erebus ice tongue is only ten metres high the icebergs aren’t very big.
When the sea ice dissipates or is swept away, waves and tidal activity start to work on the ice tongue. This, combined with internal stresses, carves the ice tongue and forms amazing ice caves.
Unfortunately, or fortunately, they are in a protected area and you can only get to see them if you are working at the US Base at McMurdo or the New Zealand Scott Base, where the caves are a popular attraction.
You can also only get to the caves by crossing the sea ice so it is only accessible part of the year.
Here is a video of a visit to the caves
Here is a video of a visit to the caves