Observations of winter aeolian transport and niveo‐aeolian deposition at crater lake, pangnirtung pass, N.W.T., Canada

Annual observations of aeolian transport in an arctic proglacial setting indicate that summer transport is minimal when frequent precipitation occurs and water levels are high, but that autumn and winter transport is much more significant than is usually assumed. Strong katabatic winds and low snowfall are typical of the winter season, so that bare frozen surfaces contribute grains to the transport load through sublimation and abrasion. During violent winter sandstorms, coarse granules are suspended up to 4 m above the surface and conventional instrumentation grossly underestimates the transport load. Most of the depositional record of this transport is erased during flooding of the sandur in the following season. Relatively light summer winds winnow out the fine fraction of the coarse, poorly to moderately sorted winter aeolian deposits, so that a lag develops on the surface of thin aeolian sand sheets lining the sandur.