Effects of topography on the spin-up of a Venus atmospheric model
Effects of topography on the spin-up of a Venus atmospheric model
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DOI：
10.1029/2006je002804
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发表时间：
2007-04-11
影响因子：
4.8
通讯作者：
Dowling, T. E.
中科院分区：
文献类型：
--
作者：
Herrnstein, A.;Dowling, T. E.
[1]我们研究了地形如何影响金星大气模型的其余部分的自旋。这些模拟是用EPIC模型进行的，它使用等熵的、跟随地形的混合垂直坐标，并用Lee等人用来在没有地形的金星模型中实现超自转的牛顿冷却轮廓来强制执行。(2005)。我们能够用我们的模型重现他们的结果，该模型是独立开发的，使用了不同的垂直坐标。这两组人都使用5度的水平分辨率，这是由合理的计算机运行时间所决定的，并不是数字收敛的主张。我们发现，地形的加入大大改变了模型自旋的演化和终态：超自转的量级从55ms(-1)减小到35ms(-1)，并且更快地达到稳定状态，用了几年而不是几十年。与Ishtar Terra有关的一个大的、稳定的涡旋形成，在0.7bar水平具有2K量级的局地水平温度异常；在高分辨率红外图像中可以观察到这样的特征。
[ 1] We study how topography affects the spin-up from rest of a model of the atmosphere of Venus. The simulations are performed with the EPIC model using its isentropic, terrain-following hybrid vertical coordinate, and are forced with the Newtonian-cooling profile used to achieve superrotation in a Venus model with no topography by Lee et al. ( 2005). We are able to reproduce their results with our model, which was developed independently and uses a different vertical coordinate. Both groups use a horizontal resolution of 5 degrees, which is dictated by the need for reasonable computer runtime and is not a claim of numerical convergence. We find that the addition of topography substantially changes both the evolution and end state of the model's spin-up: the magnitude of the superrotation is diminished from 55 ms(-1) to 35 ms(-1), and it reaches steady state faster, in a few years instead of a few decades. A large, stationary eddy associated with Ishtar Terra forms that has a local horizontal temperature anomaly of order 2 K at the 0.7 bar level; such a feature may be observable in high-resolution infrared images.