Topographic Asymmetry Across the Arctic

Aspect-dependent differences in steepness provide insight into the fate and formation of permafrost-affected landscapes, but the circum-Arctic distribution of topographic asymmetry remains unknown. The maps derived here add nuance to the notion that periglacial conditions promote steeper north-facing slopes. Only 20% of the area exhibits elevated north-south asymmetry, chiefly in rugged terrain. Across all moderate-relief landscapes, there is a bell-shaped trend with temperature. Steeper south-facing slopes are common in very cold and cool regions. In between, steeper north-facing slopes predominate. Despite multiple caveats, the bell-shaped trend with temperature suggests controls that vary with climatic factors, including permafrost conditions. The bell-shaped trend and observations of permafrost degradation further indicate that certain asymmetric transition-zone landscapes are predisposed to enhanced geomorphic activity in a warming climate.

Automated summary

The study reveals that in colder regions, south-facing slopes are steeper, while in slightly warmer regions, north-facing slopes are steeper. Approximately 20% of the area exhibits significant north-south slope asymmetry, primarily in rugged terrain.