DRivers and Impacts of Ionospheric Variability with EISCAT-3D (DRIIVE)

EISCAT-3D (DRIIVE) 的驱动器和电离层变率的影响

• 批准号: NE/W003201/1
• 负责人: Corwin Wright
• 金额: $ 38.4万
• 依托单位: University of Bath
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FW003201%2F1
• 关键词: DRivers; Impacts; Ionospheric; Variability; EISCAT

One of the biggest unanswered questions in the solar-terrestrial science that underpins Space Weather research is: How does the high latitude ionosphere vary on small scales in response to driving from above and below? An immediate practical follow-on question would be: what are the impacts of small-scale processes to the larger upper atmosphere environment? The answers to these questions are essential for understanding how Space Weather impacts on society. This area is of growing importance to the UK, as evidenced by recent investment in operational Space Weather forecasting at the Met Office and the inclusion of Space Weather in the National Risk Register. To answer these questions, we need to understand the processes that occur in the region known as the Mesosphere-Lower Thermosphere-Ionosphere (MLTI - 75-200 km altitude) and how they affect the wider coupled ionosphere-upper-atmosphere system. The ionosphere and upper neutral atmosphere are intrinsically linked: perturb one and the other changes. This has implications for our near-Earth space environment where variations in atmospheric density produce changes in the orbits of space debris, increasing the risk of unforeseen collisions; a significant natural hazard as Geospace grows more crowded. Space Weather plays a big role in modifying this region through frictional Joule heating and particle energy deposition but is not the only important driver. The weather in the lower atmosphere drives changes in the ionosphere that can be comparable to external forcing, but the relative contribution is far from understood, as the processes are under-observed. Another barrier to knowing that contribution is our inability to properly account for small scale variability, whether driven from above or below. Upper atmosphere models typically do not resolve this variability, yet we know that not doing so leads to underestimates of the magnitude of atmospheric heating by as much as 40%. This heating is a process that relies both on space weather driving and changes in the neutral atmosphere composition and dynamics. This project will use the brand new, next generation ionospheric radar: EISCAT-3D, located in northern Fennoscandia. This is part funded by NERC. It is capable of imaging a large volume of the local ionosphere and providing measurements on horizontal scales of 1-100 km. It will be unique with high vertical and temporal resolution and multipoint measurements of the ionospheric electric field vector. The field of view of the radar will cover a decent proportion of the auroral zone in latitude, such that results from the measurements made there can be applied to the wider region. We will use the unique capabilities of the radar to quantify the energy that is deposited into the MLTI from space weather events and also measure the impact of small-scale waves that propagate upwards from the lower atmosphere. We will use a range of support instrumentation, including newly deployed optics, and determine how the coupling between the neutral and ionized regimes affect the energy balance. Resolving these processes will let us establish their role in upper atmospheric heating. We will use the E3D observations together with comprehensive upper atmosphere models to determine and apply methods of correcting estimates of heating due to the small-scale changes. Using advanced models with inputs informed by the results of our observations we will determine how the small-scales affect the low altitude satellite debris field in the Earth's outer environment. This Project directly addresses two of the priority areas (and touches on others) that have been identified in the NERC Highlight Topic Announcement of Opportunity, and so answers the key question: How does the high latitude ionosphere vary on small scales in response to driving from above and below?

在支持空间气象研究的日地科学中，最大的悬而未决的问题之一是：高纬度电离层如何在小范围内变化，以响应来自上方和下方的驱动？一个迫在眉睫的实际后续问题是：小规模过程对较大的高层大气环境有什么影响？这些问题的答案对于理解空间天气对社会的影响至关重要。这一领域对英国越来越重要，英国气象局最近对空间天气预报业务进行了投资，并将空间天气列入国家风险登记册，这就是明证。为了回答这些问题，我们需要了解在被称为中层-低热层-电离层(MLTI-75-200公里高度)的区域发生的过程以及它们如何影响更广泛的耦合电离层-高层大气系统。电离层和高层中性大气本质上是联系在一起的：一个扰动，另一个变化。这对我们的近地空间环境有影响，在近地空间环境中，大气密度的变化导致空间碎片轨道的变化，增加了不可预见的碰撞风险；随着地球空间变得更加拥挤，这是一种重大的自然灾害。空间天气通过摩擦焦耳加热和粒子能量沉积在改变这一地区方面发挥了很大作用，但不是唯一的重要驱动因素。低层大气中的天气推动了电离层的变化，这种变化可以与外部强迫相媲美，但其相对贡献远未被理解，因为这些过程没有得到充分的观察。了解这一贡献的另一个障碍是我们无法适当地解释小范围的变化，无论是从上到下驱动的。高层大气模型通常不能解决这种变异性，但我们知道，如果不这样做，就会导致对大气加热幅度的低估高达40%。这一加热过程既依赖于空间天气驱动，也依赖于中性大气成分和动力学的变化。该项目将使用全新的下一代电离层雷达：位于芬诺斯坎迪亚北部的EISCAT-3D。这部分资金是由NERC提供的。它能够对大体积的局部电离层成像，并在1-100公里的水平尺度上提供测量。它将是独一无二的，具有高垂直和时间分辨率以及电离层电场矢量的多点测量。雷达的视场将在纬度上覆盖极光区的相当大一部分，这样那里的测量结果就可以应用到更广泛的区域。我们将利用雷达的独特能力来量化空间天气事件沉积到MLTI的能量，并测量从低层大气向上传播的小尺度波的影响。我们将使用一系列辅助仪器，包括新部署的光学设备，并确定中性和电离区域之间的耦合如何影响能量平衡。解决这些过程将使我们确定它们在高层大气加热中的作用。我们将使用E3D观测和综合的高层大气模式来确定和应用由于小尺度变化而对估计的加热进行修正的方法。利用先进的模型，并根据我们的观测结果提供投入，我们将确定小尺度如何影响地球外部环境中的低空卫星碎片区域。该项目直接解决了NERC重点主题机会公告中确定的两个优先领域(并涉及其他领域)，从而回答了关键问题：高纬度电离层如何在小范围内变化，以响应来自上方和下方的驾驶？

项目成果

Using sub-limb observations to measure gravity waves excited by convection.

• DOI: 10.1038/s41526-023-00259-2
• 发表时间: 2023-02-08
• 期刊: NPJ MICROGRAVITY
• 影响因子: 5.1
• 作者: Wright, Corwin J.;Ungermann, Joern;Preusse, Peter;Polichtchouk, Inna
• 通讯作者: Polichtchouk, Inna

A Comparison of Stratospheric Gravity Waves in a High-Resolution General Circulation Model with 3-D Satellite Observations

高分辨率大气环流模型中的平流层重力波与 3-D 卫星观测的比较

• DOI: 10.22541/essoar.167839981.15187275/v1
• 发表时间: 2023
• 作者: Okui H