This level will familiarize you with the frozen environment. You may remember similar missions from the first game. I guess you might be surprised to hear that you'll have biggest problems not with aliens but with Korean soldiers and that is because some of them will use similar nanosuits to your armor. You'll also have to defeat a powerful boss near the end.
1 - starting area
1 - first side objective: hovercraft
2 - finish
2 - fifth main objective: tunnel
2 - sixth main objective: boss
2 - seventh main objective: passageway
3 - first main objective: colonel Lee's location #1
4 - second main objective: colonel Lee's location #2
5 - third main objective: colonel Lee's location #3
6 - fourth main objective: Eagle squad
I guess you won't be surprised to hear that this mission will begin with a short cut-scene. Notice that you're in a different environment. There are also frozen Korean soldiers near your position.