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issn. 1000-3045. 2019. 11. 004. 输送特征分析［J］. 高原气象，39（3）：467-476. DOI：10. 7522/
曾钰婷，张宇，周可，等，2020. 青藏高原那曲地区夏季水汽来源及 j. issn. 1000-0534. 2019. 00120.

Characteristics Analysis of the Land-atmospheric Water & Heat
Exchanges over the Yarlung Zangbo Grand Canyon Region

ZHANG Qiang，WEN Jun，WU Yueyue，CHEN Yaling，LI Yueqi，LIU Zheng
（College of Atmospheric Sciences，Chengdu University of Information Technology/ Sichuan Key Laboratory
of Plateau Atmosphere and Environment，Chengdu 610225，Sichuan，China）

Abstract：By using the ECMWF Re-Analyses version5 data，the water vapor transport type over the Yarlung
Zangbo Grand Canyon area of southeastern Qinghai-Xizang Plateau（QXP）are categorized，the daily variation
characteristics of land-atmospheric water heat exchange fluxes are analyzed at different locations under different
water vapor conditions by choosing two observation stations in the Yarlung Zangbo Grand Canyon area，namely，
the Pailong Station and the Motuo Station. The results show that：The plateau monsoon period is the period of
strong water vapor transport and the warm-wet period in the Yarlung Zangbo Grand Canyon area，while the oppo‐
site is true for the Plateau non-Monsoon period. Daily variations of near-surface latent heat fluxes on typical sun‐
ny/cloudy days during the Plateau Monsoon/non-Monsoon period are more sensitive and consistent in response to
atmospheric water vapor conditions at the Motuo and the Pailong stations. The daily variation of near-surface la‐
tent heat flux under strong water vapor conditions is stronger than that under weak water vapor conditions，and
the most significant difference in daily variation of near-surface latent heat flux under different water vapor condi‐
tions is found at the low altitude and humid Motuo station，where the daily average of near-surface sensible heat
flux under strong water vapor conditions（84. 05 W·m ）is about 1. 13 times of that under weak water vapor con‐
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ditions on a typical sunny day during the non-monsoon period on the plateau，and the daily variation can reach
345. 37 W·m . Different characteristics of near-surface sensible heat fluxes at the two sites in response to differ‐
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ent water vapor conditions during the highland monsoon and non-monsoon periods. The daily variation of near-
surface sensible heat fluxes at the Pailong and the Motuo stations on typical clear days during the highland mon‐
soon period is stronger under weak water vapor conditions than under strong water vapor conditions. The daily
average and variation of near-surface sensible heat flux is most sensitive to the difference of water vapor condi‐
tions during the highland monsoon/non-monsoon period at the higher altitude Pailong station，and the daily aver‐
-2
age and diurnal range of sensible heat flux under weak water vapor conditions（32. 71 and 191. 1 W·m ）is
about 1. 66 and 1. 26 times higher than that under strong water vapor conditions under a typical sunny day during
the highland monsoon period. The weakening effect of cloud cover and water vapor on solar short-wave radiation
is greater than its own greenhouse effect. The daily variations of near-surface sensible heat fluxes at the Motuo
and the Pailong stations under weak water vapor conditions on typical cloudy days during the highland monsoon/
non-monsoon period are stronger than those under strong water vapor conditions，and the daily average values of
near-surface sensible heat fluxes at the Pailong station under weak water vapor conditions on typical cloudy days
-2
during the Plateau Monsoon/non-Monsoon period are 35. 12 and 14. 32 W∙m which are 2. 59 and 1. 27 times
higher than those under strong water vapor conditions，respectively. The existence of water vapor transport chan‐
nels in the Yarlung Zangbo Grand Canyon area，the radiation forcing of atmospheric water vapor has significant
effects on the land-atmospheric water & heat exchanges process，the energy parting at the surface is controlled
by the land surface property.
Key words：Yarlung Zangbo Grand Canyon；heat & water exchanges；water vapor transport；total atmospheric
water vapor content