Snowbed experiment species composition and hobo data for Niwot Ridge, 2012 - ongoing.

Niwot Ridge climate records indicate a trend of warmer spring and
summer temperatures and earlier timing of snowmelt. In alpine tundra
plant communities where snow cover limits growing season length, the
current climatic trend is conducive to a longer growing season. The
snowbed experiment was established in order to monitor changes in
plant cover and community composition in the alpine tundra in
response to extended summer growing season conditions. Of particular
interest are late-melting snowbed areas where plant colonization and
survival are most restricted or entirely prevented by a limited
number of snow-free days with the sunlight and temperature necessary
for plant establishment and growth. In 2012, fifteen 1 x 1 m plots were established at 5 sites where
there are persistent, late-melting snowbeds. Plots were placed along
(1) an elevation gradient and (2) a snow-cover gradient from
persistent snowbeds, where snowpack is greatest and melt-out dates
latest in the season, to wind-scoured dry meadows, where snow pack
is least and melt-out dates earliest. In 2015 the one site was
dropped from the experiment because the snowbed there was quite
different from the other four.