Your questions: Keeping safe

What happens if a big snow storm comes, where would you go? 
Keeping safe in Antarctica is very important. You have to be constantly checking that you are eating enough food (for energy), drinking enough liquid (so you don't get dehydrated) and wearing enough warm clothes. You also need to plan carefully so you don't take risks that would put you in danger.  
One of the first things that new arrivals to Scott Base do is field training, where you learn how to cope in sudden emergencies. If you were caught outside in a storm, away from a tent or hut, you could build a snow cave. You pile all your gear in a mound, cover it with snow and pack the snow down. Then you dig a tunnel to pull out your gear and make space for you to sleep in. 
Here's a very cool video of some people actually building a snow cave. 

Digging out a snow cave. Photo by Jim Barker
©Antarctica New Zealand Pictorial Collection [1970]

How do you know where the ground is that will not collapse through?

Something else you start to learn on the field training course. Around Scott Base, there are flags to show where the safe walking routes are. If you go further away, there are rules to follow about how to keep safe. But it can still be dangerous. A Canadian pilot died in January 2016 after falling into a crevasse at an Australian base. Part of the danger is hypothermia, because you might get so cold before you could be rescued. 

If you are walking on ice and there is a crevasse underneath and you fall, will you fall in water or more ice?

If you are on sea ice, there would be water underneath. But if you are on the land, the crevasse could be like a slice taken out of a glacier, with ice going a long way down.  

Survival training; practising going down a crevasse on a rope;
Antarctica NZ Pictorial Collection [1974-75], CC licence

What do you do with dangerous animals?

Well, there aren't any dangerous land animals, so that's a good start. (There aren't many land animals at all, apart from tiny ones like mites and ticks.) And there are no polar bears, either. They only live in the Arctic. 

Antarctica NZ has an environmental code of conduct which says you have to stay 10m away from any animal (unless it comes up to you), but you might want to keep a lot further away from some of them, like killer whales (orca) or leopard seals. There are some very scary stories from the early explorers about encounters with those animals. 

Leopard seal with Adelie penguin. Photo by G Court,
@Antarctica NZ Pictorial Collection, CC licence