Streamflow processes in an alpine permafrost catchment, tianshan, China

AbstractThe Cirque Basin, Tianshan, China is characterized by steep slopes, coarse surficial deposits and a cold climate that maintains permafrost at shallow depths. These conditions exert strong influences on the streamflow processes. In late winter, freezing of the infiltrated meltwater from an uneven snow cover enables ground ice formation. This renders parts of the active layer impervious to seepage, and in the spring both surface and subsurface flows can occur to supply water to the stream. In summer, the coarse materials facilitate rapid infiltration and exfiltration. Where the channel slope is steep, as in the upper basin, infiltration results in a dry stream bed but deep percolation is prevented by a shallow frost table. Exfiltration prevails in the lower basin where the channel gradient is reduced, and streamflow increases rapidly within half a kilometre, from zero to its maximum values at the gauging station. Water balance analysis yields a high runoff ratio of 0.75 for this basin and this is comparable with other tundra areas. The streamflow processes observed in this basin should be applicable to other non‐polar alpine catchments.

Streamflow processes in an alpine permafrost catchment, tianshan, China Journal Articles