Evaluation of atmospheric boundary layer–surface process relationships in a regional climate model along an East Antarctic traverse
Evaluation of atmospheric boundary layer–surface process relationships in a regional climate model along an East Antarctic traverse
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DOI：
10.1029/2011jd016441
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发表时间：
2012-05
影响因子：
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通讯作者：
A. Rinke;Yongfeng Ma;L. Bian;Yufei Xin;K. Dethloff;P. Persson;C. Lüpkes;C. Xiao
中科院分区：
文献类型：
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作者：
A. Rinke;Yongfeng Ma;L. Bian;Yufei Xin;K. Dethloff;P. Persson;C. Lüpkes;C. Xiao
在2005-2008年的区域气候模式HIRHAM中，对南极东部地区与地面气候和大气边界层相关的一些主要物理关系进行了研究和评估。在稳定条件下，不同的地面通量参数化方案所得到的风尺度感热通量与大气-地面温差之间的观测关系存在显著差异。其中一些方案在强稳定条件下降低了传热系数CH，而其他方案（如Louis方案）则没有。然而，HIRHAM的应用程序的路易斯参数化产生小CH强稳定的条件下，类似于观察和其他计划，可能是因为表面粗糙度比观察到的大得多的使用和散装理查森数不同。对于中山，观测到的辐射-云，温度-云，温度-风的关系在模式中重现，但数量上的差异是明显的。观测到的云的长波变暖效应在模式中更大，而云对下行流短波辐射的减少是模式中的两倍。该模型部分地再现了与大气解耦相关的弱风状态，但未能再现随着风的增加而增加的温度。辐射-云关系的定量差异表明，云特征的误差会导致晴天和多云条件下的下沉流净辐射显著不足。这种缺陷可能是HIRHAM表面温度强冷偏差和近地面稳定性正偏差的原因。感热通量分析和敏感性试验表明，感热通量关系的误差不是主要原因。
Some primary physical relationships related to the surface climate and atmospheric boundary layer were examined over East Antarctica and evaluated in the regional climate model HIRHAM for 2005–2008. For stable conditions, the observation-derived relationship between wind-scaled sensible heat flux and air-surface temperature difference distinctively differs between different surface flux parameterizations. Some of them decrease the heat transfer coefficient CH for strongly stable conditions, while others, such as the Louis scheme, do not. However, HIRHAM’s application of the Louis parameterization produces small CH for strongly stable conditions similar to observations and other schemes, likely because a surface roughness much larger than observed is used and the bulk Richardson number differs. For Zhongshan, the observed radiation-cloud, temperature-cloud, and temperature-wind relationships are reproduced in the model, though quantitative differences are evident. An observed longwave warming effect of clouds is larger in the model, while the reduction of downwelling shortwave radiation by clouds is twice as large in the model. The model partially reproduces an observed weak wind regime associated with atmospheric decoupling, but fails to reproduce increasing temperatures with increasing winds. The quantitative differences in the radiation-cloud relationship suggest that errors in cloud characteristics produce a significant deficiency in downwelling net radiation for clear and cloudy conditions. This deficiency is the likely cause of HIRHAM’s strong cold bias in the surface temperature and positive bias in near-surface stability. The sensible heat flux analyses and a sensitivity test suggest that errors in the sensible heat flux relationship are not the primary cause.