A storm bashed against the pillar of rock and ice projecting from the South Face of Mount Bradley in Alaska, a barrage of snow in its swirling gusts. Mark and I dove into our tent, placed on the only ledge we’d found for hundreds of feet. We had planned to spend a single night on the route. This was our third. We were 3,000 feet up, with 1,000 feet of climbing still to go. Between us we assembled a small pile: two energy bars, a half can of gas and a single freeze-dried meal. “We’re going to need these for tomorrow,” Mark said quietly, and packed the bars into a stuff sack. I looked at the nutritional information on the meal packet: 400 calories each for dinner.