Collaborative Research: Understanding Relationships between First Lightning, In-cloud Microphysics and Satellite-Observed Cumulus Cloud-top Properties

合作研究：了解第一次闪电、云内微物理和卫星观测的积云云顶特性之间的关系

• 批准号: 0813603
• 负责人: John Mecikalski
• 金额: $ 39.22万
• 依托单位: University of Alabama in Huntsville
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-15 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0813603&HistoricalAwards=false
• 关键词: Collaborative; Research; Understanding; Relationships; between

This research focuses on enhancing understanding of the inter-relationships between the Geostationary Operational Environmental Satellite (GOES) and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite observations, total lightning information, and polarimetric radar fields related to the mechanisms that initiate lightning within convective clouds (so-called first lightning). A hypothesis to be tested is that one can estimate the onset, intensity and character of lightning events (i.e. the relative amount of lightning expected, in terms of flash rates over time) in convective clouds across a region. Lightning within convective clouds is far from ubiquitous, and therefore considerable uncertainty exists as to why certain storms are prolific lightning producers, while others nearby may not be. The project goals are: (1) Perform basic research to relate GOES satellite-observed (infrared) convective cloud growth properties to the character (intra-cloud versus cloud-to-ground) and intensity of lightning in these clouds, and to the relationship to in-cloud dual-polarimetric Doppler radar-observed microphysical distributions; (2) Enhance understanding of convective regimes by describing the general characteristics of lightning and convective cloud development as observed by satellite and dual-polarimetric Doppler radar in various environments; (3) Extend current ability to nowcast (0-90 minutes) lightning events using GOES and MODIS. Intellectual Merit: The research will lead to an improved understanding of the interrelationships between lightning, cloud microphysics, and of satellite observations of growing cumulus. This research will take advantage of an exiting meteorological testbed that includes dual-polarimetric radar, lightning mapping array, GOES, MODIS and Tropical Rainfall Measuring Mission (TRMM) observations, and a mobile radar. Density of lightning will be correlated in space and time to graupel, freezing altitudes and ice distributions (all inferred from polarimetric radar), and compared to GOES cloud-top cooling rates as an estimate of in-cloud vertical mass flux, cumulus cloud growth, and cloud-top microphysics. Insights into cumulus cloud electrification, recharge, and lightning types will be subsequently developed from this research. Broader Impact: A current CI (convective initiation) forecasting technique developed by the Principal Investigators is already being evaluated within the Federal Aviation Administration's Aviation Weather Research Program and the National Weather Service. The mechanisms, therefore, are in place for this research to immediately impact a broad operational community. In addition, collaboration with other university scientists and graduate students will further extend this research to the larger academic and educational community.

这项研究的重点是加强对地球静止业务环境卫星（GOES）和中分辨率成像光谱仪（MODIS）卫星观测，总闪电信息和偏振雷达场的机制，引发对流云内的闪电（所谓的第一闪电）之间的相互关系的理解。 有待检验的一个假设是，人们可以估计一个区域内对流云中闪电事件的发生、强度和特征（即预期闪电的相对数量，以闪电率随时间的变化表示）。 对流云中的闪电远非无处不在，因此，为什么某些风暴是多产的闪电生产者，而附近的其他人可能不是，存在相当大的不确定性。 该项目的目标是：（1）开展基础研究，将GOES卫星观测的（红外）对流云生长特性对特征的影响（云内与云对地）和这些云中闪电的强度，以及与云中双偏振多普勒雷达观测的微物理分布的关系;（二）透过描述天文台观测到的闪电及对流云发展的一般特征，加强对对流系统的认识。卫星和双极化多普勒雷达在不同的环境;（3）扩大目前的能力，以临近预报（0-90分钟）闪电事件使用GOES和中分辨率成像光谱仪。智力优势：这项研究将有助于更好地理解闪电、云微物理学和卫星观测积云之间的相互关系。这项研究将利用现有的气象试验台，包括双极化雷达，闪电测绘阵列，GOES，中分辨率成像光谱仪和热带降雨测量使命（TRMM）的意见，和一个移动的雷达。 闪电的密度将在空间和时间上与霰、冻结高度和冰的分布（都是从偏振雷达推断的）相关联，并与GOES云顶冷却率进行比较，作为对云中垂直质量通量、积云增长和云顶微物理的估计。 积云带电，充电和闪电类型的见解将随后从这项研究中发展出来。 更广泛的影响：由主要研究人员开发的当前CI（对流起始）预报技术已经在联邦航空管理局的航空气象研究计划和国家气象局内进行评估。 因此，这项研究的机制已经到位，可以立即影响到广泛的业务界。 此外，与其他大学科学家和研究生的合作将进一步将这项研究扩展到更大的学术和教育界。