Never once used anything on my face through the winter. Just tighten up the good string and bite the bullet. Frostbite's never an issue because the water doesn't get below...say... 30 or so.
I could not help but go back and look at these shots of the these groms again. Those last few shots of them...each looking intently at the other. I remember me and my buddy (lost to suicide years later) doing the same thing as young groms. I miss him. Those kids are stoked and shredding!