Space weather effects on airline communications in the high latitude regions

有效的空中交通管理有赖于飞机与空中交通管制中心之间可靠的通信。然而，北极缺乏支持通过标准甚高频链路进行通信的地面基础设施(而在北冰洋上，这种链路是不可能的)，而且由于地球的弯曲，在北纬约82度以上不可能通过地球静止卫星进行通信。因此，对于高纬度飞行，有必要使用高频无线电进行通信。高频无线电依靠电离层的反射来实现绕地球曲线的长距离通信。不幸的是，高纬度电离层受到空间天气扰动的影响，这可能会扰乱通信。这些扰动起源于太阳上的事件，如太阳耀斑和日冕物质抛射，这些事件将粒子在地球磁场的引导下发射到两极周围的区域。在这种情况下，高频无线电通信可能会严重中断，飞机被迫使用更长的低纬度航线，从而增加飞行时间、燃料消耗和成本。通常情况下，为这些较长的航线着陆和加油的必要性进一步增加了燃料消耗。这项建议中描述的工作不能防止空间天气扰动及其对无线电通信的影响，但通过对这些现象的详细了解并利用这一点来提供空间气象信息服务，可以最大限度地减少对飞行业务的干扰。电离层干扰和无线电通信中断的发生遵循太阳活动的11年周期。在太阳活动的上一次高峰期间，一些事件造成了跨大西洋航线的中断。近年来，无线电通信中断的频率比我们处于太阳活动周期的低谷时要少得多。然而，在接下来的几年里，太阳活动将会增加，这将导致无线电通信问题的增加。越来越多的人使用跨极航线，以及在跨大西洋航线上需要处理更大的交通密度，这都意味着保持可靠的高纬度通信在未来将更加重要。

Efficient air traffic management depends on reliable communications between aircraft and the air traffic control centres. However there is a lack of ground infrastructure in the Arctic to support communications via the standard VHF links (and over the Arctic Ocean such links are impossible) and communication via geostationary satellites is not possible above about 82 degrees latitude because of the curvature of the Earth. Thus for the high latitude flights it is necessary to use high frequency (HF) radio for communication. HF radio relies on reflections from the ionosphere to achieve long distance communication round the curve of the Earth. Unfortunately the high latitude ionosphere is affected by space weather disturbances that can disrupt communications. These disturbances originate with events on the Sun such as solar flares and coronal mass ejections that send out particles that are guided by the Earth's magnetic field into the regions around the poles. During such events HF radio communication can be severely disrupted and aircraft are forced to use longer low latitude routes with consequent increased flight time, fuel consumption and cost. Often, the necessity to land and refuel for these longer routes further increases the fuel consumption. The work described in this proposal cannot prevent the space weather disturbances and their effects on radio communication, but by developing a detailed understanding of the phenomena and using this to provide space weather information services the disruption to flight operations can be minimised. The occurrence of ionospheric disturbances and disruption of radio communication follows the 11-year cycle in solar activity. During the last peak in solar activity a number of events caused disruption of trans-Atlantic air routes. Disruptions to radio communications in recent years have been less frequent as we were at the low phase of the solar cycle. However, in the next few years there will be an upswing in solar activity that will produce a consequent increase in radio communications problems. The increased use of trans-polar routes and the requirement to handle greater traffic density on trans-Atlantic routes both mean that maintaining reliable high latitude communications will be even more important in the future.