When cosmonauts and astronauts now return from a long-duration space mission on board the International Space Station, they are always coming home on a Soyuz capsule, landing in northern Kazakhstan. The Kazakh Steppe is known for its bitter winters (I just checked the local weather in Ayagoz, Kazakhstan and there is currently a blizzard going on with heavy snow, high winds and a current temperature of -26 C [-15 F] )
When a Soyuz lands, it usually takes at least an hour for the rescue team to arrive. But a blizzard or other unforeseen problems could leave the crew stranded for longer periods of time. So, cosmonauts and astronauts undergo special survival training, just in case. Here are some images from the latest crew to undergo the training, featuring cosmonaut Sergei Prokopyeva, ESA astronauts Thomas Pesquet and Samantha Cristoforetti. Remember that complicating any return from long-duration space flight is the weakness the space travelers will experience after six months in weightlessness.
In addition to the technical knowledge related to the landing capsule, the cosmonauts/astronauts need to practice practical skills like constructing a shelter and building a fire. They have a special emergency kit in the Soyuz which includes weapons, lights, water (6 liters for three people), dried food, first aid kit, tools and equipment that may be useful in extreme conditions, and clothing such as a heat suit, woolen cap, headset, gloves, socks and fur socks.
The Cosmonaut Training Center website says that "to successfully complete the test (training), crews have to show courage, self-discipline, perseverance, and patience." Don't worry - Samantha Cristoferri said on Google+ that the can near the fire is water, not gasoline!
ESA astronaut Thomas Pesquet, Cosmonaut Sergey Prokopiev and ESA astronaut Samantha Cristoforetti during winter survival training.