Why have space weather forecasts not improved for over a decade?

为什么太空天气预报十多年来没有改善？

• 批准号: NE/Y001052/1
• 负责人: Mathew Owens
• 金额: $ 50.41万
• 依托单位: University of Reading
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FY001052%2F1
• 关键词: Why; space; weather; forecasts; improved

The solar wind is a continual outflow of material from the Sun, which fills the solar system. Rapid changes in the solar wind conditions in near-Earth space have consequences for technologies in space and on the ground, most notably the power grid. It also poses a radiation threat to humans on high altitude flights and in space, such as future crewed missions to the moon and Mars. For these reasons, such "space weather" features prominently on the UK National Risk register; accurate space-weather forecasting a goal of critical importance.In order to mitigate against the costly, and sometimes dangerous, impacts of space weather, it is necessary to provide adequate warning time of an incoming event. As the solar wind always flows away from the Sun, forecasting further into the future effectively means starting the forecasts with information from closer to the Sun. Currently, the Met Office (and other international forecast agencies) uses remote observations of the Sun's surface and lower atmosphere in conjunction with computer models in order to forecast space weather 2-4 days into the future. Unfortunately, the accuracy with which these state-of-the-art methods can forecast the time of onset of the severe space weather is both insufficient to be useful for many applications, and has not improved for more than a decade. However, there are measurements of the solar wind being routinely made that are not currently being used by the models. Using methods developed at the University of Reading over the last 4-5 years, we have shown that solar wind forecasts can be significantly improved by ingesting these observations into the models using a technique called data assimilation (DA). We will employ our new solar wind DA methods to determine what factors most influence space-weather forecast accuracy and, consequently, what are the fundamental limits to how accurate forecasting can hope to reach. We will also adapt our solar wind DA methods to work with the Met Office's forecast models, providing a significant improvement in future space-weather forecasting. This will have wide societal benefits, as both satellite operation and the power grids can be impacted by space weather.

太阳风是来自太阳的物质的持续流出，充满了太阳系。近地空间太阳风条件的快速变化对太空和地面技术（尤其是电网）产生了影响。它还对高空飞行和太空中的人类构成辐射威胁，例如未来的月球和火星载人任务。由于这些原因，此类“太空天气”在英国国家风险登记册中占据显着位置；准确的空间天气预报是一个至关重要的目标。为了减轻空间天气造成的代价高昂、有时甚至是危险的影响，有必要为即将发生的事件提供足够的预警时间。由于太阳风总是远离太阳，因此对未来的进一步预测实际上意味着从更接近太阳的信息开始预测。目前，英国气象局（和其他国际预报机构）利用对太阳表面和低层大气的远程观测并结合计算机模型来预测未来 2-4 天的空间天气。不幸的是，这些最先进的方法预测恶劣太空天气发生时间的准确性不仅不足以用于许多应用，而且十多年来也没有提高。然而，对太阳风的常规测量目前尚未被模型使用。使用雷丁大学过去 4-5 年开发的方法，我们表明，通过使用数据同化 (DA) 技术将这些观测结果纳入模型中，可以显着改进太阳风预测。我们将采用新的太阳风 DA 方法来确定哪些因素对空间天气预报的准确性影响最大，从而确定预测准确度的基本限制是什么。我们还将调整我们的太阳风 DA 方法，以与英国气象局的预报模型配合使用，从而显着改进未来的空间天气预报。这将产生广泛的社会效益，因为卫星运行和电网都会受到太空天气的影响。