Glacier winds in the Rongbuk Valley, north of Mount Everest: 1. Meteorological modeling with remote sensing data

Autor: Tong Zhu, Ling Kang, Yu Song, Xuhui Cai, Weili Lin
Rok vydání: 2007
Předmět:
Zdroj: Journal of Geophysical Research. 112
ISSN: 0148-0227
Popis: [1] Persistent glacier winds blowing from noon to midnight in summer are present in the Rongbuk Valley, north of Mount Everest, with a maximum speed of 10 m s−1 and a vertical thickness as high as 1 km. These glacier winds may bring upper level atmosphere ozone to the surface, having a significant impact on the atmospheric environment. Such phenomena may be typical of the Tibetan Plateau, where most high mountains are covered by snow or glacier ice throughout the year. The Advanced Regional Prediction Model was used to simulate the down-valley flows, using realistic topography but neglecting synoptic winds. The modeling results agree well with the observations obtained in June 2002, revealing that the glacier winds are thermal flows primarily driven by the along-valley temperature gradient between the colder air over the glacier surface and the warmer air over surface areas covered by rock debris, which maintains air advection along the Rongbuk Valley. Downslope winds over the glacier slopes, especially from the western valley side, and the West Rongbuk Glacier, were forced by their inertia farther down into the valley and would intensify the glacier winds. The narrowing of the Rongbuk Valley could also speed up the glacier winds. Sensitivity tests showed that the detailed distribution of the Rongbuk Glacier, delineated by data from the Enhanced Thematic Mapper Plus on Landsat 7, plays an important role in glacier winds development. The glacier winds could be much weaker in winter when the area is completely snow covered.
Databáze: OpenAIRE