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| Titel |
Comparison on micrometeorology and surface energy fluxes between debris-free
and debris-covered glaciers in the southeast Tibetan Plateau |
| VerfasserIn |
Wei Yang, Yongjie Wang |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250146929
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| Publikation (Nr.) |
 EGU/EGU2017-10999.pdf |
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| Zusammenfassung |
| The knowledge of meteorology and energy fluxes on the debris-free and debris-covered
glacier is important for understanding how different glaciers behaviors heterogeneous to
regional climate change. Based on the observations during 2016 ablation season at the
debris-free Parlung No.4 Glacier and the debris-covered 24K Glacier in southeast Tibetan
Plateau, a comparative analysis was made to shed light on the micrometeorology and surface
energy fluxes and to gain knowledge about the influencing factors controlling melting process
at different type glaciers. The meteorological correlations showed that the variables including
air temperature, relative humidity and incoming longwave radiation (Lin) display a regionally
synchronous pattern, but there are notable differences in precipitation, incoming shortwave
radiation (Sin) and wind speed between two glaciers. The most striking is the difference in
precipitation, with 5 times larger in the 24K Glacier. The energy fluxes between two glaciers
display contrasting pattern due to different surface conditions and monsoonal precipitation.
More Sin was absorbed due to lower debris albedo (0.05) In spite of same amount
of total Sin and more Lin (W/m2 larger) was supplied from warm and humidity
air at the 24K Glacier. However, such excess energy supply was mainly used to
warm the debris temperature, leading to the increase of energy output by outgoing
longwave radiation and turbulent heat fluxes, rather than glacier melting. These energy
outputs are very sensitive to the debris thickness in which is less than 10 cm and
the amount of Sin, leading to significant spatial change of underneath ice melting
magnitude. At the debris-free surface at AWS of Parlung No.4 Glacier, surface
melting is mainly supplied by net shortwave radiation and turbulent sensible heat
fluxes (Hse). Comparing with energy fluxes in 2009, the reduced melting energy in
2016 on the debris-free Parlung No.4 Glacier is attributed to the decrease of Sin
and Hse by the increase of monsoonal clouds and weaken katabatic wind speed. |
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