As as a mortal, Clint doesn't possess any advanced abilities or superpowers, but he is one hell of a marksman with an uncanny ability to never miss a target once he's got it in his sights, so anything that involves projectiles, he'll be on it. His day job aside, it opens up a lot of opportunities to impress people with his party tricks, just, avoid placing bets, because he'll always win.

Well, if provisions run low, and provided he has access to a bow and arrows, then he can hunt. And, of course, if there are wildlife creatures to be hunted. He'll not be great in the terrain, because, well, so much snow, but he'll know how to survive in it, to adapt to it, so he'll have that on his side, if nothing else. He has military-like training that covers all terrain and basic survival skills, and he's been around long enough to have picked up additional things to get him by. Plus, he'll be all for helping others, if their paths' cross, so he can pass on what he knows, and that's safe to do, to help the others stranded with him as far as making sure there's food to get them by, ways to keep warm and cook, hunting for protection as well as provisions, enough first-aid knowledge to help any wounded.

He's quick, strong, and fast, and he knows how to think on his feet, so dealing with threats is something he'll be able to manage well enough. And he's had insight, as well as experience, into having his mind messed around with, so he'll have the advantage of instinct on when to stop and pause before acting if it comes to mind games, though, he is only human, and he doesn't consider himself an expert, so even he can be fooled. Probably not twice, though.

He'll know how to suffer, from hunger to suffering through the cold, and pushing through with injuries, because he's made it far enough to get to fight alongside people like Captain America and Thor, Iron Man and the Hulk, and his partner in crime, the Black Widow, and without the abilities and advantages that they have, something led him there, whether it be his determination or ability to push himself to the extremes in order to be able to keep up, whatever it is, it's enough. And he'll do anything to out-live, and, hopefully, out-smart whoever's doing this to them in order to make it back to his people, as well as the others there with him, and if he can't get them back, then he'll do whatever it takes to help keep them alive and as safe as they can be, even if it is just keeping them company over the network so they don't get cabin fever.

Tying in with that, he'll look on at as an adventure, as another mission where there are civilians in the mix to be lead to safety and protected until that can happen. He'll get somewhat of a thrill out of it, no matter how miserable, because no S.H.I.E.L.D. agent could do what they do without that in their blood, reaching out with a sense of adventure, another hurdle to work around. He's experienced the unusual, impossible, unbelievable, he's battled aliens and been possessed by a demi-god controlling his every move, and he lives to tell the tale, so a load of snow shouldn't be too hard to figure out. Right?