A team of NASA scientists has just returned from a trip to Antarctica to survey the condition of the ice at the South pole, as part of Operation IceBridge.

The agency has monitored Antarctic ice for years by satellite but that satellite, ICESat-1, was decommissioned in 2009 without an immediate replacement. ICESat-2 is due to launch in 2016, so until then NASA is using aircraft to monitor the ice instead.

Over the course of five science flights in late November, the IceBridge team covered 20,000 kilometres, gathering data on the thickness of the ice below. During the mission, on 24 November, 2013, team member Michael Studinger shot this incredible photo of a lenticular cloud floating over Mount Discovery — a stratovolcano lying at the head of McMurdo Sound.

The summit of Mount Mikeno in the Virunga Mountains

Lenticular clouds form when stable, moist air flows over a range of mountains. As the air is forced to rise, the water vapour it contains cools and condenses into a cloud. On the other side, it falls again and dissipates, leaving a lens-shaped cloud in the mountain’s wake.

In the foreground of the above photo there’s a pressure ridge, formed when two ice floes collide and push up against each other, in the same way that the Himalayas were formed by the collision of the Indo-Australian and Eurasian tectonic plates.

You can find more incredible photos from Nasa’s IceBridge 2013 expedition over on Flickr.