Gravity Wave and Seismic Signatures in the Airglow

气辉中的重力波和地震特征

• 批准号: 5037-2006
• 负责人: Lowe, Robert
• 金额: $ 1.29万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=365140
• 关键词: Gravity; Wave; Seismic; Signatures; Airglow

The night airglow comes from a layer in the upper atmosphere at a height of 80 - 100 km.  In this layer, chemical reactions involving the recombination of oxygen atoms lead to the emission of light that can be detected by instruments on the ground. Various dynamical processes in the atmosphere can lead to fluctuations in the brightness of the night airglow emissions.  We measure these fluctuations with ground-based instruments and use them to infer the nature of the processes that cause them.   Two processes of these dynamical processes will be studied in the present work.  Firstly, we will study the effects of gravity waves.  These waves are a major mechanism for transporting energy and momentum between atmospheric regions.  Understanding their nature and frequency of occurrance is important in the development of atmospheric models including numerical weather prediction models.  Secondly, we will examine the possibility that infrasonic waves generated by seismic activity can be detected in the airglow patterns we observe.  Of great interest is the possibility that airglow variations can be seen before the occurrance of the earthquake.  Such behaviour has been reported in the past but has not been convincingly verified. The nature of the variations that we study can vary greatly according to local factors such winds blowing over surface features such as mountain ranges as well as active weather patterns such as thunderstorms. As a result, we locate our instruments at widely separated locations around the world to observe in a variety of locales. Currently we have instruments both in Antarctica and within the Arctic circle in Norway.  In 2006, we will install a third instrument at a mountain site in India in a region of frequent seismic activity.

夜间气辉来自80 - 100公里高度的高层大气层，在这一层中，涉及氧原子重组的化学反应导致发射出地面仪器可以检测到的光。大气中的各种动力过程可能会导致夜间气辉发射亮度的波动。我们使用地面仪器测量这些波动，并利用它们来推断导致这些波动的过程的性质。 本文主要研究两个动力学过程：第一，重力波的影响。重力波是大气区域之间能量和动量传输的主要机制。了解重力波的性质和发生频率对发展包括数值天气预报模式在内的大气模式是很重要的。第二，重力波的影响。我们将研究由地震活动产生的次声波是否可以在我们观察到的气辉图案中被探测到。非常有趣的是，在地震发生之前可以看到气辉变化的可能性。这种行为在过去曾有报道，但尚未得到令人信服的证实。我们研究的变化的性质可以根据当地的因素而有很大的不同，例如吹过山脉等地表特征的风以及雷暴等活跃的天气模式。因此，我们将仪器放置在世界各地相距甚远的地方，以便在各种地方进行观察。目前，我们在南极洲和挪威北极圈内都有仪器，2006年，我们将在印度地震活动频繁地区的一个山区安装第三台仪器。