Thermal Structure and Composition
Thermal Structure and Composition
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热结构和成分
DOI：
10.1017/9781139060172.004
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
A. Kleinböhl
中科院分区：
文献类型：
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作者：
Michael D. Smith;S. Bougher;T. Encrenaz;F. Forget;A. Kleinböhl
在过去的二十年里，对火星大气的热结构和组成进行的观测数量和种类都有了巨大的增加。有力的地面和空间观测活动与众多航天器在火星上的成功运行相结合，这些航天器包括探路者号、火星全球探测器（MGS）、火星奥德赛号、火星快车号、火星探测漫游者号（MER）、火星侦察轨道器（MRO）、凤凰号、火星科学实验室（MSL）在水手9号和维京海盗号早期成功的基础上，以前所未有的细节来描述火星的大气。虽然仍有一些地区需要进一步观测，但有了现有的观测数据，就有可能对火星目前的气候和大气组成提出一个相当完整的概览。描述火星大气特征的两个最基本的量是大气温度（或热结构）和组成大气的气体成分。一般来说，这两个量都随时间和地点而变化，本章的目标是描述和量化空间、日、季和年际变化。这种对大气状态的描述构成了理解控制当前火星气候的所有物理过程的基础，从大气环流到沙尘暴的机制，云的作用和光化学。许多类型的观测有助于我们了解热结构和成分，这通常允许不同仪器和技术之间的验证和交叉校准。观测的主要工具是热红外探测、无线电和紫外线掩星以及近红外光谱。从火星表面，使用了数量有限的热红外探测和气象成套设备，其中通常包括近表面温度和大气压力传感器。在空气制动过程中，以及着陆器进入、下降和着陆过程中，加速度计记录提供了更多的信息。在这篇综述中，我们首先讨论了热结构，描述了现有的观测和观测到的空间和时间依赖性。接下来，我们将把注意力转向构成火星大气的气体成分，包括同位素比例的讨论。水蒸气是一种特殊情况，本章只简要地提到。第十一章将对大气中的水蒸气进行全面的讨论.最后，我们讨论了现有的火星气候数据库的审查，我们提出了一套三个参考大气的范围内的典型条件。关于火星大气的热结构和组成的早期评论可以在Zurek（1992），Zurek等人的章节中找到。（1992）和Owen（1992）在Mars（University of Arizona Press，1992）和Encrenaz（2001）、Liu et al.（2003）和Smith（2008）。
Over the past two decades there has been a vast increase in the amount and variety of observations characterizing the thermal structure and composition of the Mars atmosphere. The combination of vigorous ground-based and space-based observational campaigns with the successful operation of numerous spacecraft at Mars including Pathfinder, Mars Global Surveyor (MGS), Mars Odyssey, Mars Express, Mars Exploration Rovers (MER), Mars Reconnaissance Orbiter (MRO), Phoenix, and Mars Science Laboratory (MSL) has built upon the earlier successes of Mariner 9 and Viking to allow the atmosphere of Mars to be characterized in unprecedented detail. While there are still areas that require further observations, with the observational data now in hand it is possible to present a reasonably complete overview of the current Martian climate and atmospheric composition. Two of the most basic quantities in the characterization of the Martian atmosphere are the atmospheric temperatures (or ther-mal structure) and the composition of the gases that make up the atmosphere. In general, both of these quantities vary in time and in location, and it is the goal of this chapter to describe and quantify the spatial, diurnal, seasonal, and inter-annual variations. This characterization of the atmospheric state forms the basis for understanding all the physical processes that control the current Martian climate, from the general circulation, to the mechanics of dust storms, the role of clouds, and photochemistry. Many types of observations have contributed to our knowledge of the thermal structure and composition, and often this has allowed for the validation and cross-calibration between different instruments and techniques. The primary tools for observation have been through thermal infrared sounding, radio and ultraviolet (UV) occultations, and near-infrared spectroscopy. From the Martian surface, a limited number of thermal infrared sounding and meteorological packages that typically include sensors for near-surface temperature and atmospheric pressure have been used. Accelerometer records taken during aerobraking passes, and the entry, descent, and landing of surface landers, have provided additional information. In this review, we first discuss the thermal structure, with a description of the available observations and the observed spatial and temporal dependence. We next turn our attention to the composition of the gases that make up the Martian atmosphere, including a discussion of isotopic ratios. Water vapor is a special case and is only briefly mentioned in this chapter. A complete discussion of atmospheric water vapor is given in Chapter 11. We conclude this review with a discussion of available Martian climate databases, and we present a set of three reference atmospheres that span the range of typical conditions. Earlier reviews on the thermal structure and composition of the Martian atmosphere can be found in the chapters by Zurek (1992), Zurek et al.(1992), and Owen (1992) in Mars (University of Arizona Press, 1992) and in papers by Encrenaz (2001), Liu et al.(2003), and Smith (2008).