(1) Institute of Low Temperature Science, Hokkaido University
(4) Experimental Forest, Hokkaido University
Hydrological observations were carried out in a tundra watershed near Tiksi, eastern Siberia during summer in 1997, 1998 and 1999, and characteristics of the summer water balance were discussed. Due to strong wind in winter and low height vegetation, snowdrift is a common feature in tundra area, and it remains as snow patch until the middle of summer, supplying the meltwater to a river. In the water balance analysis, we introduced the ratio of the snow patch area to the whole watershed area as a tuning parameter, a, for taking into account the meltwater from the snow patches. Experimental watershed was 5km2 in area, and discharge was measured at the outlet of the watershed. Radiation, air temperature, humidity, wind speed and precipitation were observed at meteorological station near the watershed. Snowmelt amount was estimated using degree-day method. Because surface condition was heterogeneous in the watershed, estimation of evapotranspiration must conclude information of surface condition. In this analysis, surface conditions were classified into three types: snow patch; wet land; dry land, and mean evapotranspiration was estimated from amount of each surface condition. The obtained results are as follows: The contribution of meltwater from snow patches to discharge continued in summer after snowmelt period; Rainfall and snowmelt amount changed remarkably year to year; Major output component was discharge and evapotranspiration contributed relatively small to the output; Storage change was small to the other components.
Submittal Information
Name :
Date :
Norifumi Sato
31-May-01-05:38:23
Organization :
Theme :
Institute of Low Temperature Science, Hokkaido University
