Rolling Grant Support for a Programme of Research in Solar-Planetary and Atmospheric Physics at the University of Leicester

我们提出了一个关于地球和行星外部环境的广泛研究计划，该计划由行星磁场、外部太阳风和内部行星大气之间发生的相互作用决定。该方案将由实验工作、数据分析、理论和计算机模拟组成，可以最简单地用四个互动要素来描述。第一个要素是“日地物理”研究，将利用地面和空间实验设施检查地球磁层对来自行星际介质的高度可变的输入，即太阳风和嵌入的行星际磁场的反应。众所周知，国际货币基金组织的方向是相互作用的主要决定因素，但太阳风冲击波压力也起到了作用。将调查外部区域内发生的基本过程如何随这些输入而变化，以及所产生的影响沿外部磁力线向地球极地电离层和大气层的传播。实验研究将集中在SuperDARN雷达阵列、欧空局集群空间任务和NASA新的THEMIS任务的数据上。第二个研究领域将考虑行星外部等离子体环境中的相关现象，在这些环境中也有类似的考虑，但条件非常不同。结果就这样告知我们，并通过对地球系统的理解而得到信息。行星研究最初将重点放在木星和土星上，利用哈勃太空望远镜的极光数据和卡西尼号太空任务的现场数据。稍后，火星上的工作也将开始，为欧空局的外火星轨道器任务做准备，水星上的工作也将为比普科伦坡做准备。这项工作也将为以后对太阳系外行星外部环境的研究提供信息。在第三个研究领域，将使用SPEAR、TROMSO和HAARP高功率雷达设施在地面环境中进行新颖的主动实验。这些将首先用于通过产生可被SuperDARN雷达探测的人工散射来研究自然现象。其次，它们还将被用来以受控的方式人为地激发地球电离层和磁层中的波和振荡。这种波激发可以将连接到雷达的磁力线‘标记’到地球磁层深处，在那里它们可以被航天器探测到。通过这些手段，磁力线穿过地球外部环境的高度不确定的路径可以第一次通过实验被固定下来。第四个领域最后考虑了空间环境对地球上层大气的影响，以及在较低海拔可能影响地球气候的后续后果。这项工作将主要通过复杂的中高层大气计算机模拟及其对低海拔强迫变化和高海拔边界条件变化的反应来进行。要做到这一点，需要对现有的计算机模型进行实质性开发。这项工作还将为未来对太阳系外行星大气的研究提供信息。

We propose a broadly-based programme of research on the outer environments of the Earth and planets, shaped by the interactions that take place between the planetary magnetic field, the solar wind on the outside, and the planetary atmosphere on the inside. The programme will consist of experimental work, data analysis, theory, and computer modelling, and can be described most simply in terms of four interactive elements. The first element consists of research in 'solar terrestrial physics' in which ground- and space-based experimental facilities will be used to examine the response of the Earth's magnetosphere to the highly-variable inputs from the interplanetary medium, namely the solar wind and embedded interplanetary magnetic field (IMF). The direction of the IMF is known to be a principal determinant of the interaction, but the solar wind ram pressure also plays a role. How the fundamental processes that occur within the outer regions vary in response to these inputs will be investigated, together with the transmission of the resulting effects along outer magnetic field lines into the Earth's polar ionosphere and atmosphere. Experimental research will focus on data from the SuperDARN radar array, the ESA Cluster space mission, and the new NASA THEMIS mission. A second area of study will consider related phenomena in the outer plasma environments of the planets, where similar considerations apply but under very different conditions. Results thus inform and are informed by understanding of the terrestrial system. Planetary research will initially focus on Jupiter and Saturn, using auroral data from the Hubble Space Telescope and in situ data from the Cassini space mission. Later, work will also begin on Mars in preparation for the ESA ExoMars orbiter mission, and on Mercury in preparation for BepiColombo. This work will also inform later studies on the outer environments of extra-solar planets. In the third research area novel active experiments will be undertaken in the terrestrial environment using the SPEAR, Tromso, and HAARP high-power radar facilities. These will first be used to study natural phenomena through the production of artificial scatter that can be detected by the SuperDARN radars. Secondly, they will also be used to artificially excite waves and oscillations in the Earth's ionosphere and magnetosphere in a controlled manner. Such wave excitation can 'tag' magnetic field lines connected to the radar deep into the Earth's magnetosphere, where they can be detected by spacecraft. Through these means the highly uncertain paths that magnetic field lines take through the outer environment of the Earth can be experimentally pinned down for the first time. The fourth area finally considers the impact that the space environment has on the upper atmosphere of the Earth, and the onward consequences at lower altitudes that may effect Earth's climate. This work will be undertaken principally through sophisticated computer modelling of the middle and upper atmosphere, and its responses to changes in the forcing at low altitudes and in the boundary conditions at high altitudes. Substantial development of existing computer models is required to do this. The work will also inform future studies of the atmospheres of extra-solar planets.