When assessing a run for avalanche risk, its super useful to know its slope angle. Guessing slope angle is surprisingly tricky – so its helpful to bring an inclinometer skiing.
The PoleClinometer is an impressively ingenious sticker that lets you measure slope angle super quickly and easily.
With the PoleClinometer stuck to your ski pole its wickedly fast, easy and convenient to measure a slope angle. I probably measure 10 x as many slope angles with my Pole Clinometer than I did with my conventional inclinometer. It’s by far the lightest inclinometer on the market, and super easy to install.
The accuracy is pretty impressive. I’ve done a bunch of testing on handrails in the city, and I can consistently measure the angle of the handrail to within two degrees of what my bubble app inclinometer reads. In the backcountry without perfect slopes you’ll probably get more error from difficulty deciding which part of the slope you’re actually measuring.
When measuring the slope of a face, you’re dealing with elaborate curves not simple flat planes. For this reason, one super accurate point measurement is less useful than having many less accurate angles measured all over the face.
Because the PoleClinometer is so fast and convenient, you can make a lot more measurements and as a result gain a bigger, better idea of the slopes around you.
The PoleClinometer measures the angle of a sighted line made from your eye through the sticker to a distant point – similar to what a surveyor does. I find that this sight style makes it a lot easier to estimate angles of a curved or irregular slope.
With a convex face you can easily measure any part of the slope: With the edge of your slope as your distant point, the line between your eye and the point is tangent to the slope.
If you’re standing on a concave face it’s impossible to sight slope angles so you’ll have to estimate the steepness or take point measurements. If you are above or below the concave you can measure the slope at its steepest and flattest angles – the steepest angle is what you want to assess the avalanche risk. This isn’t possible if there’s a cornice or sharp edge that blocks the view.
The PoleClinometer comes with a neat wee installation kit with three sizes of stickers to fit all standard pole shaft diameters, transparent protective sleeve, alcohol wipes for surface prep, and really excellent instructions. The website has excellent advice like how to get the protective sleeve on difficult poles.
The PoleClinometer is so convenient and easy to use, you’ll end up making many more measurements and having a better idea of slope angles around you. Its accuracy is probably within three degrees. I’ll always have one stuck to my pole for backcountry skiing, definitely worth $12 (USD) even though its just a sticker.
Its biggest limitations are that you have to install it well – though this is pretty easy with the excellent instructions and kit- and if you need to replace your poles, you have to buy another one. It’s incapable of measuring accurate slope angles at your feet, or if you’re on a concave slope.
Hopefully the owner will sell the patent to backcountry pole makers and these will be printed on all poles in the future.
here’s another review
How it works
Well described in the instructions come with the pole, also on the website.
The PoleClinometer sticker makes different angled circles around your pole. Dangling your pole vertically aligns the circles to their respective degrees off horizontal. Lining up a circle with the hill slope, you can read off its angle.
While dangling the pole, move the pole up and down until you get your distant point between a line curving down and a line curving up. Each number is the degrees off horizontal of the line beneath the number.
In the photo below, look closely at which lines are curving which way. Line 60, 55, 50, 45, 40, 35, 30 are clearly curving up. Lines 0, 5 10 15, 20 are clearly curving down. Line 25 is almost flat, so it’s almost 25 degrees from the camera lens to the distant horizon. It curves slightly down, so my guess is that the angle is about 26 degrees. You can confidently say that the angle is 25-28 degrees.
NB: You are measuring the angle from the sticker to the horizon, its up to you to decide that this is the same angle as the slope.
Same as before but now looking downhill. The 25 degree line is pretty much flat, maybe curves down sliiightly. I would guess the angle is 25-26 degrees.
NB: Because the slope is concave, you are measuring the exact angle of the point on the edge of the hill.
Maths of the PoleClinometer
if you want a more rigorous explanation, using coordinate changes check out the PoleClinometer website here.