Auroral substorm studies, ionosphere studies using superDARN and e-POP satellite instruments, sunspot-cycle-driven space weather and links to meteorological weather

极光亚暴研究、使用 superDARN 和 e-POP 卫星仪器的电离层研究、太阳黑子周期驱动的空间天气以及与气象天气的联系

• 批准号: 403915-2011
• 负责人: Sofko, George
• 金额: $ 1.09万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=488452
• 关键词: Auroral; substorm; studies; ionosphere; using

One of the most energetic effects of the impact upon the Earth of the solar wind is the production of substorms resulting in brilliant displays of auroras and strong currents and particle motions in the ionosphere more than 100 km above ground. We plan to use ground-based instruments to study the displays, currents and motions, and then to use the upcoming Canadian e-POP satellite to study the effects from heights of 500-2000 km in and just above the ionosphere. The interaction of the solar wind with the Earth takes place in the large outer region of magnetic field - the magnetosphere -from which disturbances flow down to the ionosphere. Substorms have three stages, the growth phase, the expansive onset phase in which the auroras in the ionosphere brighten and expand poleward and east-west, and the recovery phase. Two main mechanisms have been proposed to account for the explosive onset, namely partial diversion of currents flowing from the morning to evening side of the nightside magnetosphere (the magnetotail) down to the ionosphere, and "magnetic reconnection" which transfers energy from the Earth's magnetic field to the charged particles that cause the auroras. The main purpose of the present proposal is to develop all aspects of a new substorm model I have proposed which incorporates both the above mechanisms. Although simple in principle, the model requires much development to study the processes in neighbouring regions of the nightside magnetosphere. The distorted magnetic fields in the magnetotail lead to three neighbouring layers in which the particle motions and currents of the outer two layers are opposite to those in the middle. This produces strong wave activity that leads to the magnetic reconnection that drives the onset phase. Finally, substorms are just one aspect of the Sun's changing behavior during 11-year sunspot cycles, which may soon disappear if the recent 18-year weakening of magnetic fields in sunspots continues. This last happened in 1645-1711 when European weather became very cold (the Little Ice Age). Part of this proposal is to reveal how the sunspot- cycle-related "space weather" leads to changes in the Earth's weather.

太阳风对地球影响的最大能量效应之一是产生亚暴，从而在离地面100多公里的电离层中产生耀眼的极光以及强电流和粒子运动。我们计划使用地面仪器来研究显示、电流和运动，然后使用即将到来的加拿大e-POP卫星来研究电离层内和略高于500-2000公里高度的影响。太阳风与地球的相互作用发生在磁场的大外部区域--磁层--从那里扰动向下流到电离层。亚暴有三个阶段，即增长阶段、电离层极光变亮并向东向西扩展的扩张开始阶段和恢复阶段。人们提出了两种主要机制来解释这次爆发，即从磁层(磁尾)早晚一侧流向电离层的电流部分转移到电离层，以及将能量从地球磁场转移到产生极光的带电粒子的“磁重联”。本建议的主要目的是发展我提出的一个新的亚风暴模式的所有方面，该模式结合了上述两种机制。虽然该模型在原理上很简单，但在研究夜间磁层邻近区域的过程方面需要很大的发展。磁尾中的扭曲磁场导致了三个相邻的层，其中外两层的粒子运动和电流与中间的相反。这产生了强烈的波活动，导致了驱动起始阶段的磁重联。最后，亚暴只是太阳黑子11年周期中太阳行为变化的一个方面，如果太阳黑子磁场最近18年的减弱持续下去，这种变化可能很快就会消失。上一次出现这种情况是在1645-1711年，当时欧洲的天气变得非常寒冷(小冰期)。这项提议的一部分是揭示与太阳黑子周期相关的“空间天气”如何导致地球天气的变化。