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  • Impact of 3‐D Radiation‐Topography Interactions on Surface Temperature and Energy Budget Over the Tibetan Plateau in Winter
Title: Impact of 3‐D Radiation‐Topography Interactions on Surface Temperature and Energy Budget Over the Tibetan Plateau in Winter
Abstract We incorporate a parameterization to quantify the effect of three‐dimensional (3‐D) radiation‐topography interactions on the solar flux absorbed by the surfaces, including multiple reflections between surfaces and differences in sunward/shaded slopes, in the Community Climate System Model version 4 (CCSM4). A sensitivity experiment is carried out using CCSM4 with the prescribed sea surface temperature for year 2000 to investigate its impact on energy budget and surface temperature over the Tibetan Plateau (TP). The results show that the topographic effect reduces the upward surface shortwave flux and, at the same time, enhance snowmelt rate over the central and southern parts of TP. Comparing to observations and the ensemble of Coupled Model Intercomparison Project Phase 5 (CMIP5), we found that CMIP5 models have a strong cold bias of 3.9 K over TP, partially induced by the strong reflection of shortwave fluxes. We show that the inclusion of topographic effect reduces the substantial biases of upward shortwave fluxes and surface air temperatures over TP by 13% in the CCSM4 model.  more » « less
Award ID(s):
1660587
PAR ID:
10374735
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Journal of Geophysical Research: Atmospheres
Volume:
124
Issue:
3
ISSN:
2169-897X
Page Range / eLocation ID:
p. 1537-1549
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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