How To Use Your PoleClinometer™
Here’s how to get accurate slope angle measurements.
Don’t Grip It… DANGLE IT!
Your pole is your vertical reference. Think of it like a plumb-bob. It MUST hang freely from a loose grip, or your reading won’t be accurate.
From the Side (Sighting Across the Slope)
With a side view of a slope, sight across it as shown.
Look for the PoleClinometer lines that appear to match the angle of the slope.
Here the angle of the slope appears to be about half way between the angles of the lines marked “30” and “35”, so the slope angle is around 32 or 33 degrees.
From the Top (Sighting Down the Slope)
At the top of a slope, sight down it as shown.
Position yourself so your line of sight matches the angle of the slope.
Look for the PoleClinometer lines that appear least curved in your line of sight.
Here the line marked “30” is curved slightly up, while the line marked “35” is curved slightly down, to about an equal degree, so the slope angle is around 32 or 33 degrees.
Other Methods of Use + Tips & Tricks
The two techniques described above will probably be the ones you’ll use most, but there are other ways to use your PoleClinometer too. Look for descriptions of additional PoleClinometer use modes to appear on this page in the not-too-distant future, along with some general tips and tricks for getting good accurate readings. If you come up with a creative way to use it, contact me so I can pass it along.
Color Code & Avalanche Angles
PoleClinometer is color coded to help you quickly identify slope angles that are more prone to avalanche. Here’s a summary of what the color codes mean:
Note that this is only intended as a rough guide. The range of slope angles that are prone to avalanche can vary significantly as a function of snowpack. For a more thorough understanding of how slope angle and other variables affect risk of avalanche, I highly recommend taking at least a Level 1 AIARE Avalanche Course, and reading the following books:
Staying Alive in Avalanche Terrain
by Bruce Tremper
Snow Sense: A Guide to Evaluating Snow Avalanche Hazard
by Jill Fredston
The below chart shows empirical data from a sample set of slab avalanche measurements in the Canadian Rockies. It is included here with permission directly from the pages of Snow Sense.