Space weather disruptions to satellite navigation and telecommunications: ionospheric scintillation

现代世界越来越依赖于利用全球导航卫星系统的系统，其中最广为人知的也许是全球定位系统。这些包括汽车或移动的手机中的“卫星导航”。然而，除了用于运输（公路、航空、铁路和海运）之外，全球导航卫星系统还用于其他广泛的应用，包括勘测、应急服务、农业、移动的通信和金融交易。在2011年委员会向欧洲议会和理事会提交的一份报告中，据估计，当时欧洲联盟有8000亿欧元的国内生产总值依赖于卫星无线电导航。同年，皇家工程学院的一份报告建议，直接或间接依赖全球导航卫星系统进行定位、导航或定时的服务“应将此作为其服务说明的一部分加以记录，并解释其全球导航卫星系统中断的应急计划”。我们将向我们的合作伙伴提供电离层闪烁造成的这种中断风险的全球地图，这是影响电离层的空间天气的一个主要结果。闪烁是来自GNSS卫星的无线电信号的快速变化，接收器无法“锁定”信号，因此无法将此信号用于导航或定时。闪烁在高纬度和低纬度都很常见，但有时会延伸到中纬度，如英国，欧洲和美国。例如，在2003年10月的“万圣节”太阳风暴期间，美国联邦航空管理局广域增强系统空中导航网络瘫痪了30个小时，主要原因是闪烁。我们的工作是及时的，因为GNSS的使用是如此普遍，以至于最近（2017年6月）Innovate UK的一份报告估计，仅在英国，GNSS中断五天的影响就将超过50亿英镑，直接损失和连锁延迟。其中1.1亿英镑用于铁路部门，这是我们的项目合作伙伴特别感兴趣的领域。https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/619544/17.3254_Economic_impact_to_UK_of_a_disruption_to_GNSS_-_Full_Report.pdfhttp://lasp.colorado.edu/home/wp-content/uploads/2011/07/lowres-Severe-Space-Weather-FINAL.pdfhttp://www.raeng.org.uk/publications/reports/global-navigation-space-systems

The modern world is increasing reliant on systems that make use of Global Navigation Satellite Systems (GNSS), perhaps the most well know of which is GPS. These include the 'Satnav' in cars or mobile phones. However, in addition to its use in transport (road, air, rail and maritime), GNSS is used a wide range of other applications including surveying, emergency services, agriculture, mobile communications and financial transactions. In a 2011 report from the Commission to the European Parliament and the Council it was estimated that 800 billion euro of gross domestic product (GDP) in the European Union, was then dependent on satellite radio navigation. A Royal Academy of Engineering report of the same year suggested that Services that depend on GNSS for positioning, navigation or timing (PNT), either directly or indirectly, "should document this as part of their service descriptions and explain their contingency plans for GNSS outages". We will provide, to our partners, global maps of risk of such outages, caused by ionospheric scintillation, a major result of space-weather affecting the ionosphere. Scintillation is where there are such rapid changes in the radio signal from a GNSS satellite that a receiver cannot 'lock on' to the signal and so cannot use this signal for navigation or timing. Scintillation is common at both high and low latitudes, but can on occasions extend to middle latitudes such as the UK, Europe and the United States. For example, during the 'Halloween' solar storm in October 2003, the United States Federal Aviation Administration Wide-Area Augmentation System (WAAS) network for air navigation was disabled for 30 hours, primarily due to scintillation. Our work is timely as the use of GNSS is so ubiquitous that a recent (June 2017) Innovate UK report estimated that the impact in the UK alone to a five-day disruption to GNSS would be in excess of £5 billion through direct losses and knock-on delays caused. £110 million of this was in the rail sector, an area of particular interest to our project partners. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/619544/17.3254_Economic_impact_to_UK_of_a_disruption_to_GNSS_-_Full_Report.pdfhttp://lasp.colorado.edu/home/wp-content/uploads/2011/07/lowres-Severe-Space-Weather-FINAL.pdfhttp://www.raeng.org.uk/publications/reports/global-navigation-space-systems