Altitude's Effect on Survival
Above 2,000m, altitude significantly affects human physiology and survival calculations. Cold, reduced oxygen, and increased UV radiation all compound survival challenges.
Water Needs
At altitude, respiratory water loss increases dramatically as your body works to humidify cold, dry air. Add 30% water requirement per 1,000m above sea level. At 4,000m, a person who needs 2L/day at sea level actually needs approximately 2 × 1.3 × 1.3 = 3.38L/day — nearly 70% more.
Calorie Needs
Digestion is less efficient at altitude, and breathing work increases caloric demand. Add 5-10% per 1,000m. Cold also increases basal metabolic rate for thermoregulation.
Boiling Point
Water boils at progressively lower temperatures as altitude increases. At 4,000m, boiling point is approximately 85°C. At 7,000m, it's approximately 75°C. This affects cooking times and effective sterilization.