Collaborative Research: Balloon Campaign to Quantify Thunderstorm Effects on the Global Electric Circuit

这笔赠款将量化雷暴活动作为地球全球电路驱动因素的作用。将在几天的时间内获得晴朗天气垂直电场和电流密度所需的测量结果。利用平流层气球平台上成熟的双朗缪尔探头技术得到的高空、高空、地形等影响下的晴天电场和垂直电流密度的时间序列，将与同期全球雷暴活动的特征进行比较。随着最近陆基全球闪电探测网络的发展和特点，现在有可能在几分钟的时间尺度上反演全球雷暴面积及其不确定性。这项拟议工作的目标是以前所未有的准确性和深度测试这一假设，即雷暴活动是全球电路的主要驱动因素。智力上的优点。近100年前，C.T.R.威尔逊提出雷暴是全球电路的重要驱动力。要实现这一目标，需要对晴天电场的驱动因素进行定量评估。由于长期难以测量雷暴、带电云层或其他中层大气电流源，这一目标仍然难以实现。此外，关于全球电路对雷暴源变化的短期响应的观测工作非常有限。这一提议将在100秒量级的时间尺度上检验这样的联系假设。对全球活跃雷暴面积和垂直晴朗天气电流密度这两个时间序列进行直接比较，将使这一经典问题取得重大进展。由于高时间分辨率的测量比以前的研究有了实质性的进步，这项工作可能会带来关于全球电路的新见解和新问题。研究生的论文研究将作为拟议努力的结果而得到支持。此外，每年夏天还将支持一名本科生参加与气球飞行部署有关的分包合同工作。学生将接受有关仪器的开发和校准、现场战役后勤、整理和分析多种类型的数据以及作为理解测量方法的建模的培训。这笔赠款将为正在进行的全球电路建模工作提供重要的测量结果，并可能提供见解。我们对雷暴驱动组件理解的预期改进，对于在理解其他全球电路变化方面取得进展也是至关重要的，例如太阳风效应、太阳质子事件或大范围大气温度变化。如果全球雷暴活动和平流层垂直电流密度之间的牢固关系如赠款所预期的那样被确定，这将为使用少量仪器气球监测全球雷暴活动的前景打开可能性。

This grant would quantify the role of thunderstorm activity as a driver of Earth's global electric circuit. The required measurements of the fair weather vertical electric field and current density would be obtained over a period of several days. The time series of the fair weather electric field and vertical current density at high altitude, above weather, orographic, and other influences, obtained by using the well-proven technique of double Langmuir probes on a stratospheric balloon platform would be compared to properties of the contemporaneous global thunderstorm activity. With the recent development and characterization of ground-based global lightning detection networks, it is now possible to retrieve global thunderstorm area, and its uncertainty, on a timescale of minutes. The objective of the proposed work is to test the hypothesis, at unprecedented accuracy and depth, that thunderstorm activity is the primary driver for the global circuit. intellectual merit. Nearly 100 years after C. T. R. Wilson suggested thunderstorms are an important driver of the global electric circuit. Achieving this goal would require a quantitative evaluation of the drivers for the fair weather electric field. This goal has remained elusive due to a long-standing difficulty in measuring the various candidates: thunderstorms, electrified clouds, or other middle atmosphere current sources. Furthermore, there has been only very limited observational work on the short time response of the global circuit to variations in the thunderstorm source. This proposal will test thus connection hypothesis, at times scales of order 100 seconds. A straightforward comparison of the two time series of global active thunderstorm area and vertical fair weather electric current density would enable significant progress on this classic question. Because the high time resolution measurements are a substantial advance over previous investigations, this work will likely lead to new insights and questions about the global electric circuit. A graduate student's dissertation research would be supported as a result of the proposed effort. Moreover, an undergraduate student participating in the sub-contract effort relating to the flight deployment of the balloons each summer would be supported as well.Students will be trained in development and calibration of instrumentation, field campaign logistics, collating and analyzing multiple types of data, and modeling as a means to understand measurements. This grant would provide important measurements, and likely also insights, for ongoing efforts to model the global electric circuit. The anticipated improvement in our understanding of the thunderstorm driver component is also critical to achieving progress on understanding other global electric circuit variations such as from solar wind effects, solar protons events, or large scale atmospheric temperature change. If a robust relation between global thunderstorm activity and stratospheric vertical current density is identified as expected from the grant, this would open the possibility to the prospects of being able to monitor total global thunderstorm activity using a small number of instrumented balloons.