The avalanche terrain exposure scale

ATES Ratings & Risk Tolerance


What is an ATES Rating?

ATES stands for Avalanche Terrain Exposure Scale.

This is a standardized model used in Canada to convey the complexity of the Avalanche Terrain one will be exposed to during the course of an ice climb or backcountry ski or split tour. The model represents only avalanche terrain characteristics, without consideration for the snowpack.

Both terrain and snowpack need careful consideration. Our job is to communicate our assessments to you so that you are included, and empowered to play an informed role in our risk management strategy for your day with us. 

ATES Rating Levels:


For each of the above ratings, specific terrain characteristics will apply. See the table below for more information:

ATES Ratings for Ice Climbers

complex Terrain & Risk tolerance: 

Understanding an ATES Rating prior to booking an ascent with our Guides, informs how we discuss and communicate risk levels with respect to avalanche terrain on a Guided Ice Climbing ascent. 

Our Guiding  team is well versed with Waterfall Ice Climbing ascents in COMPLEX rated terrain, however our preference is only to entertain these ascents when snowpack hazard is rated LOW or MODERATE, lacks Persistent Weak Layers (PWL) and further lacks other complexity which would serve to increase our uncertainty regarding avalanche hazard or conditions.

Generally speaking, you should be aware that COMPLEX rated terrain serves to INCREASE the likelihood that an avalanche will occur, and your exposure and vulnerability will be high. 

Generally, if you are new to ice climbing, we would suggest spending some time in SIMPLE, and CHALLENGING rated terrain before diving into a COMPLEX rated ascent. This will allow you time to see first hand what complexities exist in the terrain, and increase your exposure slowly and over time. This allows for a more informed acceptance of increased risk. 



avalanche Rescue Training & Equipment:

On each of our ice climbing programs that take place in avalanche terrain, all Guests will be required to be trained in the use of, and to carry essential companion (avalanche) rescue equipment. This will include an avalanche transceiver, a probe and shovel. This training will be provided by your Guide at the start of any trip booked taking place in avalanche terrain.

Further, and AST 1 & AST 2 Course are essential skills for all backcountry travelers and will help to further prepare you for ascents taking place in avalanche terrain.