Page 174 - Çevre Şehir ve İklim Dergisi İngilizce - Özel Sayı

Determination of Potential Avalanche Release Areas, Avalanche Mobile Application and
Preparation of Avalanche Hazard Maps in Türkiye; the Case of Palandöken Ski Centre

For the detection of potential avalanche starting zones, remote sensing
methods were utilized. Through the use of topographic parameters, potential
avalanche starting zones were identified through the method developed by
Bühler et al. (2013) and adapted by Yıldız and Akkuş (2022) Figure 6).

Figure 6. The algorithm used in the detection of potential avalanche starting zones.
The main input of the algorithm is the Digital Terrain Model (DTM). DTM is
a digital model formed through the use of location and elevation data about
a particular region of the Earth, displays the topography and land features
of the region in three dimensions. This model represents the land features
in the region comprehensively (Akgül et al., 2016). The up-to-date 5-meter
DTM data used in the study was provided from The Erzurum Metropolitan
Municipality.
Other algorithm parameters include topographic features such as slope,
elevation, roughness, and curvature (Figure 7). These features play a significant
role in determining whether an area is a potential avalanche starting zone.
Surface roughness is one of the fundamental factors playing an important role
in the adhesion of the snow cover to the ground (Ancey, 2001). Roughness
can influence the likelihood of avalanches by preventing the formation of
continuous and weak snow layers (Schweizer et al., 2003). Areas with roughness
values smaller than 0.03 were selected as the roughness parameter. Areas with
low roughness have a high probability of avalanches (McClung and Schaerer,
1993). The minimum and maximum slope values were determined as 28° and
55°, respectively. Large destructive avalanches occur within this slope range.
Avalanches generally do not occur in areas with slopes less than 28° because
the shear strength of the snow layer does not exceed the tensile strength.
In areas with slopes greater than 55°, large avalanches do not occur due to
the limited snow accumulation (Ancey, 2001). The minimum elevation values

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