摘要：An analysis is made of changes in basal ice crust layer characteristics from snow cover
surveys made at 958 Russian stations since 1966. The analysis revealed that substantial
changes have occurred in response to two competing processes: an increase in thaws
associated with strong regional warming and an increase in the duration of the basal ice
layer presence on the ground, and a shortening of the snowmelt period associated with a
decrease in basal ice layer event frequency and severity. The latter appears to be
the more significant process over the past 40 years. Our findings support the
notion that the entire spring snowmelt process has become shorter in duration and
more intense when taking into account a concomitant trend toward increasing
snow depths over large regions of Russia. A more intense spring melt period has
important consequences for spring flood dynamics and deserves further study.
