‘Modelling the Arctic Boundary Layer: An Evaluation of Six Arcmip Regional-Scale Models using Data from the Sheba Project’
‘Modelling the Arctic Boundary Layer: An Evaluation of Six Arcmip Regional-Scale Models using Data from the Sheba Project’
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“北极边界层建模：使用示巴项目数据对六个 Arcmip 区域规模模型进行评估”
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
M. Shaw
中科院分区：
文献类型：
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作者：
M. Tjernström;M. Žagar;G. Svensson;J. Cassano;S. Pfeifer;A. Rinke;K. Wyser;K. Dethloff;Colin G. Jones;T. Semmler;M. Shaw
北极中部气候变化的一个主要信号是海冰的融化。这取决于大气和海冰之间的相互作用，而海冰又严重依赖于表面的动量、热量和水分的交换。在评估气候变化情景的现实性时，了解气候模拟中模拟这些交换的质量至关重要。六个最先进的区域气候模型在北极西部运行了一年，在一个共同的领域，包括北冰洋（SHEBA）实验冰漂移轨迹的表面热收支。地面变量，地面通量和对流层低层的垂直结构进行了评估使用的数据从SHEBA实验。所有模型都由相同的横向边界条件、海冰分数以及海水和海冰表面温度驱动。地面气压、近地面气温、比湿和风速与观测结果吻合较好，但准确度依次下降。风速在某些模型中存在系统偏差，高达每秒几米。考虑到问题的复杂性，地表辐射通量也令人惊讶地准确。湍流动量通量在大多数模型中平均来说是可以接受的，但是湍流热通量大多是不可靠的。它们与观测到的通量的相关性原则上是微不足道的，它们在一年内积累的值比观测到的大一个数量级。典型的瞬时误差很容易与观测到的净大气热通量具有相同的数量级。鉴于大气-冰相互作用对这些通量误差的敏感性，必须相当谨慎地看待气候变化情景中的冰融化。
A primary climate change signal in the central Arctic is the melting of sea ice. This is dependent on the interplay between the atmosphere and the sea ice, which is critically dependent on the exchange of momentum, heat and moisture at the surface. In assessing the realism of climate change scenarios it is vital to know the quality by which these exchanges are modelled in climate simulations. Six state-of-the-art regional-climate models are run for one year in the western Arctic, on a common domain that encompasses the Surface Heat Budget of the Arctic Ocean (SHEBA) experiment ice-drift track. Surface variables, surface fluxes and the vertical structure of the lower troposphere are evaluated using data from the SHEBA experiment. All the models are driven by the same lateral boundary conditions, sea-ice fraction and sea and sea-ice surface temperatures. Surface pressure, near-surface air temperature, specific humidity and wind speed agree well with observations, with a falling degree of accuracy in that order. Wind speeds have systematic biases in some models, by as much as a few metres per second. The surface radiation fluxes are also surprisingly accurate, given the complexity of the problem. The turbulent momentum flux is acceptable, on average, in most models, but the turbulent heat fluxes are, however, mostly unreliable. Their correlation with observed fluxes is, in principle, insignificant, and they accumulate over a year to values an order of magnitude larger than observed. Typical instantaneous errors are easily of the same order of magnitude as the observed net atmospheric heat flux. In the light of the sensitivity of the atmosphere–ice interaction to errors in these fluxes, the ice-melt in climate change scenarios must be viewed with considerable caution.