You could try taking a second, or a third, card with you.
That's probably standard practice for a pro; however, I consciously limit myself to the 77 frames that I get on the D700 with each of my usual cards. Why? because if I shoot more, then I have to wade through more stuff of which I shall reject the vast majority. It takes up too much life.
It's worse than film for me now in amateur status: with film, at least I would have been conscious of cost, but with digital it's only time that can bring the sense of reality, the cost of time wasted in the pursuit of what? It's very difficult to believe that photography brings its own reward, or if it does, I must have been a very naughty chap at some time.
Now that I think of it, perhaps that's the benefit/payback of amateur landscape shooting on sheet flm: you get to consider things more clearly, the relative value, the proportionality between waiting and clicking.
Rob C