Interannual variability of the atmosphere/snow interaction over the Eurasian continent during the spring season and its relation to the monsoon period
M. E. Hori (1)
(1) Graduate School of Environmental Sciences. University of Tsukuba
Interannual variability of the spring snow cover over the Eurasian continent and its
relevance towards the following monsoon season has been investigated using the NOAA/
NESDIS northern hemisphere weekly snow-cover chart and in-situ measurement of snow-
depth derived from the Historical Soviet Daily Snow Depth Version 2 (HSDSD) dataset.
Interannual variability of snow cover in the western Russian region has a strong correlation
with the January NAO (North Atlantic Oscillation) and a signal of a strong positive/negative
NAO remains as a emanating early/late snow melt in the region which persists until April.
While NAO itself has little or no auto-correlation for period longer than 1 month, a consistent
lag correlation was seen, where an EU-like wave-guide pattern following the NAO dipole
matures during March, which in turn allows an anomalous heat advection from the Atlantic to
alter the land surface condition. In the following April, a barotropic atmospheric anomaly
responsible for the adiabatic heating in the region can be seen. While such large-scale
atmospheric teleconnection can be seen accompanying the snow anomaly, its effect can no
longer be seen past May, which could suggest that its influence towards the monsoon onset
or its maturity can be marginal.
Submittal Information
Name :
Date :
Masatake E. Hori
08-Aug-04-16:42:06
Organization :
Theme :
Graduate School of Environmental Sciences. University of Tsukuba