How to detect crevasses from space

Antarctica is the most hostile environment on the Earth and safety is our number one priority when working on the ice. The danger of hypothermia, frostbite and crevasses are obvious – a scientific measurement is not worth to risk our lives and jump over a crevasse ! But how do we minimize these risks in practise ?

 

The Antarctic Field Training is mandatory for everyone who comes to Ross Island. It’s a thorough education in the use of our survival equipment and only the beginning of a proper risk assessment. Lessons like Extreme Cold Weather clothing, Skidoo and generator repairs, usage of cooking stoves as well as pully-systems for crevasse fall rescue are practised indoors at first. But it is during the ‘Shakedown’ when we camp out on the ice near McMurdo Station and practice these skills outdoors. With such an experienced team like ours, lot’s of tips and tricks are constantly exchanged between us. For example, always bring a small shovel into your tent in case you get snowed in over night and you have to dig your way back out in the morning. Or wear your lipstick on a chord around your neck to avoid losing it in the large number of pockets in your clothes. But there is so much more that we can do before heading to the field to minimize the risk of injury.

Satellites regularly observe what happens on Antarctica’s ever changing surface. Some of them take pictures like your phone that show us opening surface crevasses from a bird’s eye perspective. But what if a crevasse is hidden beneath a thin layer of snow and not visible on the surface ? Radar satellites send out a signal that penetrates into the snow and shows us how thick snow bridges across these crevasses are. If we detect any crevasses in the radar images, we then draw them onto a map and exclude these areas from our travel routes.

 

So if we can see into the snow with satellites, why do we have to go to Antarctica in the first place ? It is because these radar satellites are so high up in the sky ! They will never send out a signal that is strong enough to go all the way through the ice and see what is going on beneath the ice. For this reason we travel to areas in Antarctica which show the most rapid changes on the surface. We then bring scientific instruments that are strong enough to penetrate all the way to the ice base and beyond, such as Ground Penetrating Radar or active seismics.

 

We then measure with these instruments in areas that we consider crevasse free from our satellite data analysis (the green areas in the two maps above). Within these areas, we still travel with linked skidoos or even roped up on skis to minimize any remaining risk. And in the case somebody would still fall into a crevasse, we practise crevasse rescue first indoors and later on a safe practise crevasse near McMurdo.

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1 Response to How to detect crevasses from space

  1. polar.rack says:

    I like your new outfit!

    Like

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