The Maritime Continent Thunderstorm Experiment

本文对热带辐合带（ITCZ）的一个地区进行了两个雷暴季的闪电观测。选择澳大利亚达尔文作为活动地点是因为该国在季风季节的形成阶段经常发生雷暴。1996年11月初至11月底在达尔文举行了第一次宣传活动。第二次运动于1997年11月中旬至12月中旬进行。观测的主要项目是利用干涉仪观测重建雷暴云内的闪电通道。由于我们配备了基线长度为15 km的两套干涉仪系统，闪电通道的三维成像已基本实现，为了定量地获得闪电多次放电的发展特征，本文主要对第一个台阶先导和后续先导进行了二维分析。第一步领导者和随后的领导者作为时间的函数的领导者进展的速度。计算了平均传播速度，并从传播速度的角度分析了阶梯型先导、镖型先导和镖型阶梯型先导之间的差异。并对多点笔画与经典多点笔画的特征差异进行了比较。根据达尔文的观测结果，我们可以得出结论：典型的多点放电和多点放电的云内放电起始位置基本相同，记录到了许多从云顶向低电离层放电的红精灵，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.