Figure 4. Sediment yield (grey) and discharge (blue) summed up over each decade. The evolution of the proglacial zone derived from time-series maps (fig. 3) was interpreted towards the likely impact on sediment yield. In the 1960s, the lake trapped a lot of sediment but its trap efficiency decreases with proceeding aggradation. The valley floor exposed since the early 1950s is characterized by a very low slope gradient. We assume that the sediment delivery ratio has decreased with increase exposure of the valley floor. The significant increase in discharge since 1980s is in good agreement with higher temperatures observed.
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Uploaded: Mar2 13