Driving space weather forecasts with real data

点击翻译按钮获取中文摘要

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.