From October to April, snow is part of the environment of Lake Michigan
coastal dunes. For example, Muskegon, MI, receives an average of
268 cm (106 inches) of snow each year.
The amount of snowfall
received by a coastal dune system in a year varies according to
location and temperature and moisture conditions. Lake-effect snowfalls
increase the amount of snow along the coast (compared to locations
further inland), and they may result in adjacent dune systems receiving
very different amounts of snow.
1971-2000 monthly normals as published in the
Climatography of the United States No. 20 available from
the National Climatic Data Center at www.ncdc.noaa.gov.
Snow protects beach and dune surfaces from wind erosion. The protection
may be short-lived as wind removes the snow before moving the underlying
sand. The transport and deposition of mixtures of snow and sand
are called "niveo-aeolian".
Snowcover tends to be
highly variable on beach and dune surfaces. The snow may disappear
shortly after it falls or it may accumulate at a location and persist
for weeks or months. Exposed locations such as the windward slopes
of dunes tend to have the least (and most-quickly removed) snow
on them. Sheltered locations such as depressions and the lee slopes
of the dunes tend to accumulate deep snow drifts that remain for
long periods of time.
Snow protects the lower parts of the windward slope
of this parabolic dune from wind erosion. Slopes at the top of the
dune are bare because wind swept the snow away. There are deep drifts
of snow and sand over the top of the dune. (North Beach Park parabolic
dune in January 2005.)