My first altimeter watch was the Casio ARW-320 back in 1993. This analog-faced watch was all black with bright yellow buttons. The small digital window showed the altitude (up to a whopping 13,200 ft.), barometer (in mb only) and depth (to 98 ft.). This little wonder was my sidekick on many treks in Washington’s Cascade mountains. I religiously dialed in the altimeter’s reference altitude from our home at 325 ft. The ARW-320 was, at the time, one of the coolest altimeter watches of the day and I wore it through college until it disappeared. I don’t know what ever happened to that watch, but I was bummed losing it.
I then stepped up to the Suunto Vector (a.k.a. the Hockey Puck). The Vector was by far the most advanced altimeter watch of the day, but it came with a price–it’s HUGE size. This thing is behemoth, but it’s still one of Suunto’s top selling watches because despite it’s size, it’s super light and comfortable to wear. And, it works great!
Since the Vector, I’ve thoroughly tested and owned several of the latest altimeter watches from Polar, Timex, Origo, HighGear and Suunto. They all work essentially the same way; translating barometric pressure changes into altitude changes. Yes, an inexact science, but it’s the best there is (aside from cumbersome GPS watch technology, but we won’t go there). Lets dig into the technology behind altimeter watches and why you would want one in the backcountry.
I caught up with Ryan Hamsho, International Sales Manager for HighGear to get some specific information on how altimeters work and why you should have one. I’ve include some of his thoughts below.
How Altimeter Watches Work
Lets first get into how altimeter watches work. The simple explanation is that the higher you go, the less atmosphere is above you, the lower the air pressure is, so the higher the altitude. Altimeter watches use the atmospheric pressure as the method to modify the altitude up or down. Most current altimeter watch models track altitude changes in 3 ft. (1 meter) increments.
Because altimeter watches rely on the actual pressure reading for altitude measurement, most altimeter watches display both the adjusted-for-sea-level pressure reading and absolute air pressure–so as not to confuse you too much when you compare readings to what you see on TV or in the paper, which is adjusted for sea level.
Ryan Hamsho of HighGear, shared the following on how altimeter watches work:
An altimeter does not actually measure altitude directly, but rather just atmospheric pressure. So an altimeter is actually a barometer created for a specific purpose. The altimeter uses the changes in atmospheric pressure to determine the changes in altitude. Why does pressure change with altitude? Simply put, the pressure at any given point in the atmosphere around the earth is a result of the weight of the atmosphere above it (pulled down by gravity). For this reason, the higher in the atmosphere you are, the less atmosphere you have above, and the less pressure exerted on you.
He went on to say that the best way to calibrate an altimeter watch is to adjust your reference altitude on a regular basis–daily if you want it as accurate as possible. The best way to know your exact altitude anywhere in the world is by using Google Earth. Google Earth provides the most accurate altitude readings by searching and clicking in your exact location. See below for the exact altitude of the base of Main St. in Park City, UT (7040 ft.).
Keep in mind that altimeter watches are not scientific instruments. They are merely gauges to give you the best estimate on the current altitude. If kept properly calibrated during a day that has fairly stable weather, they should prove to be very accurate overall. In varying weather conditions, you will see some variation. Again, it’s essential to know the reference altitude to get back on track.
As a side note, I once had a customer purchase a Timex altimeter watch from the now defunct FeedTheHabit.com Online Store. He was a real estate agent from Florida and he wanted to measure exact variances in altitude to know which properties were more desirable. Remember… he was in Florida where every foot counts. I wish I would have known that before he made the purchase. Needless to say, he returned the watch because it wasn’t consistently accurate without daily user calibration. And, that’s not the intended purpose of an altimeter watch.
Why Should You Have an Altimeter Watch?
Today’s outdoor enthusiast wants to know all the details of their adventures. Handheld GPS units and altimeter watches are now commonplace in the backcountry and with good reason. They can be helpful tools when navigating mountain peaks or cross-country travel because most of them also feature a digital compass and thermometer–all handy features to help you analyze your surroundings and keep track of where you are as well as the current and upcoming weather.
Lets go back to Ryan from HighGear to answer this question from his perspective:
We are an information and curiosity-driven society. Therefore, there are several reasons one might want a wrist or hand-held altimeter (besides the obvious: that they need a time piece) and each reason is based upon a specific application (such as Hiking, Climbing, Mountain Biking and Skiing). Examples of these applications can have varying levels of seriousness. For the hiker, it may be for reasons such as monitoring the altitude for curiosity sake to carefully monitoring the barometric pressure for reasons that may be tied to seeking shelter before the next front begins to move in. In this case, the altimeter could be used as a weather station in addition to its many other functions (time, alarm, chronograph etc.).
For the climber, the altitude is relevant to determine the amount of vertical ascent or descent surmounted in minutes and hours leading to the determination of whether or not they will make an ascent/descent before the sun goes down. Further to that, there is the ability to track total ascent/descent in a 24 hour period of time.
The applications are similar for the skier and mountain biker, but the numbers accumulate in a much quicker fashion. It may be as well that a skier or biker is interested in their vertical speed. The altimeter in cooperation with the chronograph will provide this feedback. All feedback can then be logged and reviewed for future reference.
So, depending upon the type of outdoor activity, the usefulness of the altimeter watch can vary from simple curiosity during an afternoon hike, to a matter of life and death for an alpinist trying to summit a high-altitude peak within a certain time window.
Why I Use an Altimeter Watch
I like using my altimeter watch to track my backcountry skiing and mountain biking travels. It’s interesting to track your vertical ascent/descent on a mountain bike ride, or your overall vertical ascent/descent during a 3-hour backcountry ski trip. And, most models allow you to track your total ascent/descent over a period of time–say, the ski season. A few years back, during the FeedTheHabit.com Dueling Vert Contest our own Kendall Card skied 40,000 vertical feet in a single day. All tracked with his handy-dandy Suunto altimeter watch.
For me, it’s more about knowing how fast and how much–not so much a matter of life and death.
What to Look For in an Altimeter Watch
I’ve used many altimeter watches in my day and have found Suunto watches to be the best in the business as far as durability, functionality and looks. HighGear is a relative newcomer to the industry (started in 1999) and has made huge inroads in the altimeter watch market with plenty to offer at great pricepoints. All HighGear models all feature a Swiss pressure sensor to ensure the most accurate barometric pressure calibration.
If you’re in the market for a new altimeter watch, there are many models to choose from. Here are a few tips to keep in mind before buying one.
My Altimeter Watch Tips:
- Head to your local REI to try them on–they are typically much larger than you think (this goes for women especially).
- Even though some may seem quite large, they all wear pretty well (e.g. you won’t notice their size so much over time).
- Get one with a mineral glass face to avoid scratching.
- I prefer those with rubber straps for use in all outdoor activities. I like to run, bike, hike and ski with my altimeter watch, so I don’t need a bulky metal band to get in my way.
- Unless you are really into analysis, don’t spend extra money on one that allows you to download data to your computer. None of them work on a Mac (my biggest gripe) and you likely won’t use it as much as you think.
- Suunto and HighGear are the market-leaders and are the safest bets as far as quality, durability and functionality. The Suunto Core and HighGear Altis Ti are the latest models.
- If you’re looking for one that also features heart rate functionality, the Polar AXN is a great option.
The latest models from Suunto and HighGear are pictured above. The Suunto Core ($249 – $599) and the HighGear Altis TI ($300) are great options for anyone looking for a nice looking, everyday watch that is also a highly-functional wrist-top computer/altimeter.
EDITOR’S NOTE (03 Feb 2017): This article was published way back in 2007 and while watches have changed a lot since then, many altimeter watches remain essentially the same. Many now offer better web-based tools or companion mobile apps. That said, a great altimeter watch is always a nice tool to have in the backcountry.