Glacier winds in the Rongbuk Valley, north of Mount Everest: 2. Their role in vertical exchange processes
| Autor: | Ling Kang, Weili Lin, Yu Song, Tong Zhu, Xuhui Cai |
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| Rok vydání: | 2007 |
| Předmět: |
Atmospheric Science
Daytime Meteorology Soil Science Aquatic Science Oceanography Atmospheric sciences Atmosphere Geochemistry and Petrology Tributary Earth and Planetary Sciences (miscellaneous) Dispersion (water waves) Earth-Surface Processes Water Science and Technology geography geography.geographical_feature_category Ecology Lead (sea ice) Front (oceanography) Paleontology Humidity Forestry Glacier Geophysics Space and Planetary Science Geology |
| Zdroj: | Journal of Geophysical Research. 112 |
| ISSN: | 0148-0227 |
| Popis: | [1] High ozone concentrations, combined with low humidity and strong, persistent glacier winds, were found at the surface of Rongbuk Valley, north of Mount Everest, with sharply increased ozone concentrations in their vertical profiles. Glacier winds and their roles in vertical exchange of the atmosphere were investigated numerically to understand the phenomena. A Lagrangian particle dispersion model was used to carry out numerical experiments (forward-in-time simulations) and footprint analysis (backward-in-time simulations). The meteorological data inputs for these experiments were derived from the Advanced Regional Prediction System. Results showed that glacier winds may lead to significant downward transport of 1.5–2 km during the daytime from the northern slopes of Mount Everest. Glacier winds could advance down through the valley, with strong upward motions shown as a rolling up in front of their leading edge. Combining with upslope winds at two sidewalls of the valley or up-valley winds of tributaries, the lifting flows produced strong mixing of the atmosphere to a depth of approximately 3 km. Three-dimensional footprints derived from the particle dispersion model for the observational site, Rongbuk Monastery, clearly show influence from the mountainside of Mount Everest and from the southern part of the valley. The vertical extension of influence was as much as 2–3 km. Good correlation was found between the influence height and the ozone concentration. All the simulation results strongly indicate that the glacier winds and their related vertical exchange processes “pump down” ozone-rich air from upper levels to the surface of the valley. |
| Databáze: | OpenAIRE |
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