Ablation Hollows - Grinnell Glacier

Sun Cups, Ablation Hollows, whatever you call them, I just think they are cool! I was fascinated with these surface snow forms during my hiking through Glacier National Park. They are formed during dry conditions during snow melt in alpine areas that receive direct sun during the melting season (insulation). High points on the snow evaporate water molecules more slowly than the depression areas, where water collects as it melts, deepening the depression. Dirt and debris can help speed up the process. I became obsessed with finding the most unique shaped sun cups during my travels. These were next to Grinnell Glacier.
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