Water Ice Clouds in the Atmosphere of Mars

稀薄的水冰云经常出现在火星的大气中，与地球不同的是，火星的温度低到足以形成二氧化碳冰云。该项目将涉及使用开放大学火星全球环流模型来研究火星云周期[1]。火星大气中的尘埃、水蒸气和冰都是通过风传播的。它们通过吸收和释放辐射相互作用，进而影响大气温度和风的模式。大气图1:2018年全球沙尘暴期间（左）和随后没有全球沙尘暴的年份，火星气候探测仪对水冰不透明度的纬度高度分布的卫星观测。温度决定了可凝结物质凝结成冰或升华成冰的地方，而尘埃作为冰粒的凝结核起着进一步的作用。2018年，火星经历了一场全球性沙尘暴，当时火星的大部分地区都被一层由全球范围的尘埃活动造成的尘埃所覆盖。在这种极端事件中，水蒸气和水冰云的分布被显著改变，导致水在大气中的输送到比正常情况下高得多的高度。这种水的“上升”被认为与火星大气层顶部的水的整体损失有关。了解水在一系列尘埃活动下的行为，将使水的损失率可以在几个火星年的时间内计算出来

Thin water ice clouds are often seen in the atmosphere of Mars and, unlike Earth, temperatures reach sufficiently low for carbon dioxide ice clouds to form as well. This project will involve the use of the Open University Mars global circulation model to investigate the martian cloud cycle [1]. Dust, water vapour and ice are transported by winds in the martian atmosphere. They interact through absorbing and emitting radiation, affecting atmospheric temperatures and wind patterns in turn [2]. Atmospheric Figure 1: Satellite observations from the Mars Climate Sounder of the latitude-altitude distribution of water ice opacity during the 2018 global dust storm (left) and in the subsequent year with no global dust storm.temperatures determine where condensable species freeze into ice, or ice sublimates, and dust plays a further role as condensation nuclei for ice particles.In 2018, Mars experienced a global dust storm, when most of the planet was enshrouded in a layer of dust resulting from global-scale dust activity. During such extreme events, the distribution of water vapour and water ice clouds is modified significantly, resulting in the transport of water to much higher altitudes in the atmosphere than is normally possible. This 'uplift' of water is believed to be linked to the overall loss of water from the top of the atmosphere of Mars. Understanding the behaviour of water under a range of dust activity will allow water loss rates to be calculated over time for several Mars years