Large Scale Lower Ionosphere Remote Sensing

大规模低电离层遥感

• 批准号: 0634661
• 负责人: Steven Cummer
• 金额: $ 29.84万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-06-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0634661&HistoricalAwards=false
• 关键词: Large; Scale; Lower; Ionosphere; Remote

Under previous NSF funding the PI has developed and successfully demonstrated a remote sensing tool capable of measuring lower ionospheric electron densities over wide geographic regions with a minimum of ground based instrumentation based on radio sounding of very low frequency radiation from lightning strokes. As part of this effort, broadband VLF/ELF data has been recorded at a Duke University site for the last five years. In addition, the group has designed and constructed two portable VLF/ELF sensor and data acquisition systems that have been used in some recent experimental campaigns in Colorado (2005), and Northern and Southern Brazil (2005 and 2006). The thrust of this new research project is to use these existing data sets together with data from new targeted measurement campaigns to provide quantitative estimates of the lower ionosphere electron density variability over a wide range of geographic locations and time scales. The program will pursue a number of specific research goals: 1) measure mid-latitude variability and structure and determine to the degree possible the processes that drive this variability; 2) measure high and low latitude D and E region profiles, with particular emphasis on measurements in the South Atlantic magnetic anomaly region where high energy particle precipitation effects are expected to be especially significant, 3) measure the altitude profiles of different classes of lightning-produced ionospheric perturbations to answer long-standing questions about the mechanisms responsible, 4) measure E region layer variability and spatial structure, and 5) develop the technique into an autonomous distributed instrumentation system that would fit into a distributed instrument array concept. The research is devoted largely to understanding large scale atmospheric variability and its effects, and thus is by its nature closely tied to important societal issues such as global climate change. Graduate as well as undergraduate students will be involved in the research program.

在国家科学基金会以前的资助下，PI开发并成功演示了一种遥感工具，该工具能够利用最少的地面仪器，通过对雷击产生的甚低频辐射进行无线电探测，测量广阔地理区域的低电离层电子密度。 作为这项工作的一部分，在过去五年中，杜克大学的一个站点记录了宽带甚低频/极低频数据。 此外，该小组还设计和建造了两个便携式甚低频/极低频传感器和数据采集系统，用于最近在科罗拉多（2005年）和巴西北方和南部（2005年和2006年）进行的一些实验活动。 这一新研究项目的主旨是利用这些现有数据集以及新的有针对性的测量活动的数据，对广泛的地理位置和时间尺度上的低电离层电子密度变异性提供定量估计。 该计划将追求一些具体的研究目标：1）测量中纬度的变化和结构，并尽可能确定驱动这种变化的过程; 2）测量高纬度和低纬度D和E区域的剖面，特别侧重于南大西洋磁异常区域的测量，预计在该区域高能粒子降水效应特别显著，3）测量不同类别的闪电产生的电离层扰动的高度剖面，以回答长期存在的有关机制的问题，4）测量E区层的变化和空间结构，以及5）将该技术发展成一个自主的分布式仪器系统，该系统将适合分布式仪器阵列概念。 该研究主要致力于了解大尺度大气变化及其影响，因此其性质与全球气候变化等重要社会问题密切相关。 研究生和本科生将参与研究计划。