Using your altimeter watch more effectively

More and more climbers are carrying altimeter watches. To turn it from an amusing novelty into a truly useful mountaineering tool, follow these tips:

• Recalibrate your altimeter at regular intervals. When you are at an obvious terrain feature such as peak, saddle or lake, get out the topo map and take a moment to set your watch elevation to the “real world”. All team members should do the same.
• Having everyone’s watches calibrated correctly becomes especially important when your team is trying to locate a specific elevation to make a route finding choice, such as: “At elevation 8,700 feet, traverse west to find the descent notch and rappel station”  If all watches are more or less the same, these route finding decisions are a lot easier to make.
• Keep an eye on your altimeter when you’re in camp. If you’re not moving and the altimeter reading has dropped, that might be a good thing - it means barometric pressure is increasing (high pressure system), which might bring clear weather. Conversely, if your watch tells you the lake you are camped by has “risen” from 7,100 feet to 7,170 feet in a few hours, it typically means that low pressure has arrived and might bring with it unsettled weather.  If all team members get in the habit of noting elevation every few hours in camp, it’s easier to compare readings with each other to confirm your “forecast”.
• - A rule of thumb for rising altimeter readings: If your elevation has changed 40-60 feet upwards over 3 hours, keep an eye out for lowering clouds. If it’s gone up 60-80 feet consider a new route, and if it’s climbed by more 80 feet in 3 hours, head for the cars.

From The Mountaineering Handbook by Craig Connally (available in our library at the Mazama Mountaineering Center)