The Global Circuits Paradox

全球电路悖论

• 批准号: 1945871
• 负责人: Earle Williams
• 金额: $ 80.58万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-01 至 2025-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1945871&HistoricalAwards=false
• 关键词: Global; Circuits; Paradox

The long-term sustainability of Earth calls increasingly for a global perspective. This research involving simultaneous measurements of the two global circuits is decidedly global in nature. The two globally invariant (at any given time) quantities under study are (1) the ionospheric potential, representing the totality of electrified weather and (2) Schumann resonance activity, the global totality of lightning, both of which are experienced by all of humanity. Thunderstorms and lightning are both threats to all human activity, and so deserve to be monitored. The monitoring of the Earth’s Schumann resonances lends itself naturally to international cooperation. Both global electrical circuits have been shown to be responsive to surface air temperature on a variety of time scales, with much relevance on longer time scales to fossil fuel consumption and global warming given these natural frameworks for global monitoring. The observed trends will be of value to policy makers. The interest in the variable source strengths of continental “chimneys” (continental scale regions of strong convection) is also directly linked to the large-scale circulation of the atmosphere, and hence global weather patterns are likely linked with the global circuit variations under investigation here. Thunderstorms are important players in global warming because they produce large areas of cirrus cloud that affect incoming solar radiation, and also redistribute water vapor from the planetary boundary layer to the upper troposphere where it is radiatively more important. A critical aspect of global heat balance also lies with tropospheric aerosol and this study is the first to take on the monitoring of cloud condensation nuclei (CCN) on the spatial scale of the continental chimneys.A large body of evidence, some of it a century old, supports the view that the ionospheric potential characterization of the DC (“Direct Current”) global electrical circuit is maximum over the diurnal cycle in Universal Time (UT) when the American continent is electrically predominant near 19-20 UT. In contrast, a comparable body of evidence shows that global lightning activity, and the AC (“Alternating Current”) global circuit (aka, Schumann resonances) is maximum when Africa is electrically predominant (14-15 UT). This apparent contradiction is referred to hereafter as the “global circuits paradox”. This research is aimed at a resolution of this paradox. The thesis of this investigation is that the “global circuits paradox” has long gone unresolved because essential quantities have not been examined in comparisons of contributions from America and Africa, the dominant chimneys driving the global circuits. Thermodynamic contrasts have previously been examined and fall short in resolving the paradox. Electrified shower clouds were identified as possible fundamental sources additional to thunderstorms for the DC global circuit by C.T.R. Wilson, but careful comparisons between America and Africa are only recently possible with satellite and lightning observations. Increased pollution in the form of CCN have been shown to increase lightning flash rate in thunderstorms in both observations and models, but only recently have CCN been accessible on the continental scales relevant to the global circuits. In this study, coordinated measurements of the DC and AC global circuits when Africa and America are most prominent, together with electrified shower clouds and CCN (and with appropriate controls on thermodynamic quantities) to resolve the global circuits paradox.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

地球的长期可持续性越来越需要全球视角。 这项研究涉及两个全球电路的同时测量，在本质上是决定性的全球性。研究中的两个全球不变（在任何给定时间）量是（1）电离层电位，代表带电天气的总量，（2）舒曼共振活动，全球闪电的总量，这两个量都是全人类所经历的。雷暴和闪电都是对所有人类活动的威胁，因此值得监测。对地球舒曼共振的监测自然有助于国际合作。 这两个全球电路已被证明是在各种时间尺度上对地表空气温度的响应，在更长的时间尺度上与化石燃料消耗和全球变暖有很大的相关性，因为这些天然的全球监测框架。 观察到的趋势将对决策者有价值。对大陆“烟囱”（大陆尺度强对流区域）的可变源强度的兴趣也与大气的大尺度环流直接相关，因此全球天气模式可能与本文研究的全球环流变化有关。雷暴是全球变暖的重要因素，因为它们产生大面积的卷云，影响入射的太阳辐射，并将水蒸气从行星边界层重新分配到对流层上层，在那里它的辐射更重要。 全球热平衡的一个关键方面也在于对流层气溶胶，这项研究是第一次在大陆烟囱的空间尺度上监测云凝结核（CCN）。大量的证据，其中一些已有世纪的历史，支持这样的观点，即直流电的电离层电位特性当美洲大陆在19-20 UT附近占电优势时，直流电（“直流电”）全球电路在世界时（UT）的昼夜周期内最大。相比之下，一个可比较的证据表明，全球闪电活动和AC（“交流电”）全球电路（又名舒曼共振）在非洲占主导地位时（14-15 UT）最大。这一明显的矛盾在下文中被称为“全局电路悖论”。本研究旨在解决这一悖论。 本研究的主题是，“全球电路悖论”长期以来一直没有得到解决，因为在比较美国和非洲的贡献时没有检查基本数量，而美国和非洲是驱动全球电路的主要烟囱。热力学对比以前已经被检查过，并没有解决这个悖论。带电的阵雨云被确定为除了雷暴之外的直流全球电路的可能的基本来源。威尔逊说，但美洲和非洲之间的仔细比较只是最近才有可能通过卫星和闪电观测。在观测和模型中，CCN形式的污染增加已被证明会增加雷暴中的闪电率，但直到最近才在与全球电路相关的大陆尺度上获得CCN。在这项研究中，协调测量的直流和交流全球电路时，非洲和美洲是最突出的，与带电的阵雨云和CCN（并与适当的控制热力学量），以解决全球电路paradox.This奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。