Driving space weather forecasts with real data

空间气象是近地太阳风的各种条件造成的，对地球和空间技术，特别是电力基础设施、通信、地球观测和全球定位系统卫星有一些不利影响。我们对这些技术的依赖日益增加，这使得对可靠预报空间天气的需求日益增加。NERC在预测和减轻这类自然灾害的科学方面发挥着核心作用，英国气象局目前正在开发自己的空间气象预报系统，先进的空间气象预报依靠一系列数值模型来模拟从太阳到地球的扰动传播。目前，这个模型的耦合系统是由太阳光球层的磁场观测驱动的。这是用来模拟太阳日冕中的磁场结构。不幸的是，这只提供了关于扰动速度或密度的非常间接的信息，这意味着对它们的到达时间和特性的估计没有很好的约束。最近开发的日光层成像仪（HI）仪器允许首次连续观测太阳和地球之间的太阳风结构。我们建议使用这些直接的太阳风测量来驱动空间天气预报模型链，这将大大提高预测近地太阳风条件的技能。这种新的预报方案将需要从HI数据估计太阳风的速度和密度。太阳风磁场信息仍将通过现有的日冕磁场建模方法获得。密度将从HI观察到的结构的绝对亮度导出。速度将需要通过连续的HI图像跟踪太阳风特征。作为公民科学项目Solar Stormwatch的一部分，这最初将由人类观察员执行。在项目后期，这一跟踪过程将完全自动化，从而能够分析更多的HI数据，并使该方案更容易过渡到业务预报用途。拟议的三年工作计划包括全面开发和测试新的预测方案。在项目结束时，该计划将移交给英国气象局。然后，预计它将通过UKMO与美国空间天气预报中心的密切合作在国际上得到采用。

Space weather, the result of variable conditions in the near-Earth solar wind, has a number of adverse effects on Earth- and space-based technologies, particularly power infrastructure, and communication, Earth-observation and GPS satellites. Our increasing reliance on such technologies drives an increasing need to reliably forecast space weather. NERC has a central role in the science of forecasting and mitigating such natural hazards, and the UK Met Office (UKMO) is currently developing its own space-weather forecasting system.Advanced space-weather forecasting relies on a chain of numerical models to simulate the propagation of disturbances from the Sun to the Earth. Currently, this coupled system of models is driven by observations of the magnetic field at the solar photosphere. This is used to model the magnetic field structure in the solar corona. Unfortunately this provides only very indirect information about the speed or density of disturbances, meaning estimates of their arrival time and characteristics are not well constrained. The recently developed Heliospheric Imager (HI) instruments allow the first continual observations of the solar wind structure between the Sun and the Earth. We propose to use these direct solar wind measurements to drive the chain of space-weather forecast models, which should provide a vast improvement of the skill in which the forecast of near-Earth solar wind conditions. This new forecast scheme will require the solar wind speed and density to be estimated from HI data. Solar wind magnetic field information will still be derived by the existing method of coronal magnetic field modelling. Density will be derived from the absolute brightness of structures observed by HI. Speed will require solar wind features to be tracked through consecutive HI images. This will initially be performed by human observers, as part of the citizen science project, Solar Stormwatch. Later in the project, this tracking process will be fully automated, allowing analysis of a much greater quantity of HI data and for the scheme to be more readily transitioned into operational forecast use. The proposed 3-year work plan covers the full development and testing of the new forecast scheme. At the end of the project, the scheme will be transitioned to the UK Met Office. It is then expected to be adopted internationally through the UKMO's close collaboration with the Space Weather Prediction Center in the US.