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: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=529772
• 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.

太阳风对地球产生的最强烈的影响之一是产生亚暴，导致极光的灿烂展示，并在离地面100多公里的电离层中产生强电流和粒子运动。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500-2000公里高度及其上方的影响。太阳风与地球的相互作用发生在磁场的大外围区域——磁层——扰动从这里向下流向电离层。亚暴有三个阶段，即生长阶段、电离层极光变亮并向两极和东西方向扩展的膨胀开始阶段和恢复阶段。人们提出了两种主要机制来解释爆炸的发生，即从夜侧磁层（磁尾）的早晨到晚上的电流部分转移到电离层，以及“磁重联”，将能量从地球磁场转移到导致极光的带电粒子。本建议的主要目的是发展我提出的一个新的亚暴模型的所有方面，该模型结合了上述两种机制。虽然这个模型在原理上很简单，但要研究夜侧磁层邻近区域的过程，还需要进一步发展。磁尾中扭曲的磁场导致三个相邻的层，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，导致磁重联，驱动起始阶段。最后，在11年的太阳黑子周期中，亚暴只是太阳变化行为的一个方面，如果最近18年的太阳黑子磁场减弱继续下去，这种变化可能很快就会消失。最后一次发生在1645年至1711年，当时欧洲的天气变得非常寒冷（小冰河时期）。这项计划的一部分是揭示与太阳黑子周期相关的“太空天气”是如何导致地球天气变化的。