North Polar Dust Storms in Early Spring on Mars
North Polar Dust Storms in Early Spring on Mars
复制标题
火星早春北极沙尘暴
DOI：
10.1006/icar.1998.6060
复制
发表时间：
1999
期刊：
影响因子：
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通讯作者：
Steven W. Lee
中科院分区：
文献类型：
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作者：
P. James;J. Hollingsworth;M. Wolff;Steven W. Lee
摘要1996-1997年哈勃太空望远镜对火星的观测涵盖了火星北方半球的整个春季，该地区的地理位置非常适合观测北极地区。本文报道了在此期间的尘埃活动的观测。当地的尘埃活动发生在早春期间升华的北极帽边缘附近，这包括当地的尘埃云，类似于维京海盗人在南极帽边缘附近看到的尘埃云，以及不寻常的弧形尘埃特征，似乎代表了一种新型的尘埃现象。这些尘埃弧可能解释了Rima Tenuis裂缝，这是火星地面观测者偶尔看到的。对火星大气环流模式对北方早春季节进行的数值模拟分析，为深入了解北极帽后退附近高纬度地区的合理气象背景提供了依据。这些哈勃观测扩展了火星上当地尘埃活动似乎很常见的地理和季节范围。结合图像分析和模型计算支持的假设，这些沙尘暴是风的结果与移动的季节性帽，解除灰尘暴露在帽在二氧化碳升华。
Abstract Observations of Mars during 1996–1997 by the Hubble Space Telescope covered the entire spring season in the northern hemisphere of Mars, which was favorably positioned for viewing the north polar region. This paper reports observations of dust activity during this period. Local dust activity occurred near the edge of the subliming north polar cap during early spring; this included local dust clouds, similar to those seen by Viking near the edge of the south polar cap, and unusual, arc-shaped dust features that seem to represent a new type of dust phenomenon. These dust arcs may explain the Rima Tenuis rift, which has been occasionally seen by groundbased observers of Mars. Analysis of numerical simulations from a Mars general circulation model for the early northern spring season have provided insights into the plausible meteorological background at high latitudes in the vicinity of the retreating north polar cap. These Hubble observations extend the geographic and seasonal ranges during which local dust activity seems to be common on Mars. The combination of image analysis and model calculations support the hypothesis that these dust storms are the result of winds associated with fronts moving across the seasonal cap that lift dust exposed on the cap during CO 2 sublimation.