An eight-year climatology of the martian northern polar vortex
An eight-year climatology of the martian northern polar vortex
复制标题
火星北极涡旋八年气候学
DOI：
10.1016/j.icarus.2023.115864
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发表时间：
2024
期刊：
影响因子：
3.2
通讯作者：
Streeter P
中科院分区：
文献类型：
--
作者：
Streeter P
火星极地大气的特点是存在极地涡旋，这是行星大气中常见的冬季两极上空的寒冷和孤立的空气区域。极地涡旋通过与大气示踪剂和更广泛的环流的相互作用而具有重要的气象影响。反过来，它们已被证明受到大量大气尘埃负荷（例如沙尘暴）的影响。我们利用火星天气和气候的广泛再分析数据集（开放访问火星同化远程探测；OpenMARS）来研究最近八个火星年（火星年（MY）28-35（2006-2021））火星北极涡旋的季节性和年际行为。我们发现，北极涡旋在其结构和演化方面表现出高度的年际可重复性，但在出现大型（区域和全球规模）沙尘暴期间除外。此类风暴会对北极涡旋造成显着扰动，将其压缩至极地并减小其半径。然而，并非所有沙尘暴都有相同的影响。我们发现，大型沙尘暴的季节性时间似乎是决定其对北极涡旋影响的关键因素。靠近南方夏至发生的风暴比发生在春分附近的风暴影响更大。我们认为，这种季节依赖性是由于背景经向环流的结构造成的，该环流在南部夏至前后处于最强强度和纬度延伸。如果环流已经更强且纬度延伸范围更大，则由尘埃引起的加热对现有环流的增强会产生更大的影响，而如果风暴发生在环流较弱且纬度延伸范围较小的时期，则影响同样较小。
The martian polar atmosphere is characterised by the presence of polar vortices, regions of cold and isolated air over the winter poles common to planetary atmospheres. The polar vortices have important meteorological effects via their interactions with atmospheric tracers and the broader circulation. In turn, they have been shown to be affected by large atmospheric dust loadings such as from dust storms. We make use of an extensive reanalysis dataset of Mars’ weather and climate (Open access to Mars Assimilated Remote Soundings; OpenMARS) to investigate the seasonal and interannual behaviour of Mars’ northern polar vortex over eight recent martian years, Mars Years (MY) 28–35 (2006–2021). We find that the northern polar vortex shows a high degree of interannual repeatability in its structure and evolution, with the key exception of during the presence of large (regional and global scale) dust storms. Such storms cause significant perturbations to the northern polar vortex, compressing it towards the pole and reducing its radius. However, not all dust storms have equal impacts. We find that the seasonal timing of large dust storms appears to be the key factor determining their impacts on the northern polar vortex. Storms occurring closer to southern summer solstice have greater impacts than those occurring closer to equinox. We propose that this seasonal dependence is due to the structure of the background meridional circulation, which is at its greatest strength and latitudinal extension around southern summer solstice. The enhancement of this existing circulation by dust-induced heating allows greater impacts if the circulation is already stronger and more latitudinally extended, and impacts are likewise lesser if the storm occurs during a period with a weaker and less latitudinally extended circulation.
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DOI：
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发表时间：
2003
期刊：
影响因子：
--
作者：
M. McIntyre
通讯作者：
M. McIntyre
火星环形极地涡旋的稳定性
DOI：
--
发表时间：
2017
期刊：
影响因子：
--
作者：
W. Seviour;D. Waugh;R. K. Scott
通讯作者：
R. K. Scott
空间不均匀非绝热效应对火星环形极涡演化的作用
DOI：
--
发表时间：
2018
期刊：
Icarus (New York, N.Y. 1962)
影响因子：
--
作者：
M. Rostami;V. Zeitlin;L. Montabone
通讯作者：
L. Montabone
DOI：
10.1017/9781139060172.009
发表时间：
2017-06
期刊：
--
影响因子：
--
作者：
J. Barnes;R. Haberle;R. Wilson;S. Lewis;J. Murphy;P. Read
通讯作者：
J. Barnes;R. Haberle;R. Wilson;S. Lewis;J. Murphy;P. Read
火星环形极涡的形成原因是什么？
DOI：
--
发表时间：
2016
期刊：
影响因子：
--
作者：
A. Toigo;D. Waugh;S. Guzewich
通讯作者：
S. Guzewich