Martian and terrestrial dust devils: Test of a scaling theory using Pathfinder data
Martian and terrestrial dust devils: Test of a scaling theory using Pathfinder data
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DOI：
10.1029/1999je001037
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发表时间：
2000-01
影响因子：
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通讯作者：
N. Renno;A. Nash;J. Lunine;J. Murphy
中科院分区：
文献类型：
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作者：
N. Renno;A. Nash;J. Lunine;J. Murphy
火星探路者气象站记录了风、压力和温度波动，这些波动被解释为尘暴：在结缔羽流底部形成的暖核涡旋。我们应用尺度理论[Renno et al., 1998]，该理论是为了解释陆地尘暴观测而开发的，以测试这种解释的有效性，并为火星尘暴的一般特征提供简单的物理解释。该理论基于热机的热力学，并预测了连接涡旋的中心压力和风速。我们的研究结果如下：对于记录最充分的候选事件（sol 25），观测到的风和气压波动与模型预测的一致，因此加强了对该案例作为尘暴的解释。然而，其他一些候选者，虽然记录较少，但也与着陆器上方或附近的尘暴经过一致。在其他溶胶上观察到的温度波动使得尘暴比气象包测量的温度波动大一个数量级。我们的理论预测的最强沙尘暴的中心气压差约为 50 Pa，风速约为 60 m s−1。最强的尘暴能够扬起灰尘，因此支持对选定的探路者图像的解释，即显示尘暴在着陆器视野范围内通过。
The Mars Pathfinder meteorological station recorded wind, pressure, and temperature fluctuations that have been interpreted as dust devils: warm-core vortices that form at the bottom of connective plumes. We apply a scaling theory [Renno et al., 1998], developed to explain terrestrial dust devil observations, to test the validity of this interpretation and to provide a simple physical interpretation of the general characteristics of Martian dust devils. The theory is based on the thermodynamics of heat engines and predicts the central pressure and the wind speed of the connective vortices. Our findings are as follows: For the best documented candidate event (sol 25), observed wind and pressure fluctuations are consistent with those predicted by the model and hence strengthen the interpretation of this case as a dust devil. A number of other candidates, less well documented, however, also are consistent with passage of a dust devil over or near the lander. Temperature fluctuations observed on other sols permit dust devils an order of magnitude larger than the ones measured by the meteorology package. The strongest dust devils predicted by our theory have a central pressure deficit of about 50 Pa and wind speed of about 60 m s−1. The strongest dust devils are capable of lofting dust and hence support the interpretation of selected Pathfinder images as showing the passage of dust devils within sight of the lander.