The Maritime Continent Thunderstorm Experiment

在热带辐合带(ITCZ)的一个地区进行了两个雷暴季节的闪电观测。澳大利亚达尔文之所以被选为活动地点，是因为它在季风季的积聚阶段经常发生雷暴。达尔文的第一次运动于1996年11月初至11月底举行。第二次运动是在1997年11月中至12月中进行。观测的主要项目是利用干涉仪观测重建雷云内部的闪电通道。由于我们配备了两套基线长度为15公里的干涉仪系统，可以对雷电通道进行三维成像，为了定量地获得多次击穿时雷电放电的发展特征，主要对阶梯先导和后续先导进行了二维传播分析。得到了第一级领导和后续领导的领导进展速度随时间的变化关系。计算了步行者、省道步行者和省道步行者的平均速度，并从传播的角度分析了步行者与省道者之间的差异。WC注意到经典多笔画与多点笔画的特征差异。根据达尔文的观测，我们可以得出结论：经典多次击打和多点击打的云内放电的起始位置基本相同，记录到了许多红色精灵，它们是从云顶到电离层低层的放电，这是额外的观测结果。

Lightning observations in a region of the inter tropical convergence zone (ITCZ) were carried out durring two thunderstorm seasons. Darwin Australia was chosen for the campaign site because of its frequent occurrence of thunderstorms during the building up stage of its monsoon seasons. The first campaign in Darwin was held from early November through end of November in 1996. The second campaign was conducted from mid November through mid December in 1997. The main item of observations was reconstruction of lightning channels inside thundercloud by means of interferometer observations. Since we equipped two systems of interferometer with the base line length of 15 km, three dimensional imaging of lightning channels was besically available.To obtain features of the progression of lightning discharges for multiple strokes quantitatively, two dimensional analysis for stepped leader propagation are mainly given for first stepped leader and subsequent leaders. The velocity of leader progressions were obtained for both the first stepped leader and subsequent leaders as a function of time. We also calculated the average velocities, and learned the discrepancy among stepped leaders, dart leaders and dart stepped leader from the aspects of their propagation. Wc leaned the discrepancy of the characteristic difference between classic multiple strokes and multi-point strokes. According to the observations in Darwin we can conclude that the location of the initiation of discharges inside clouds for both classic multiple strokes and multi point strokes are basically same.Many Red Sprites which are the discharges from the cloud top to the lower ionosphere were recorded, and this was the additional observations.