Investigation of Convective Cloud Processes as Part of the North Dakota Tracer Experiment

计划于1993年夏季进行的北达科他州示踪器实验将集中于继续研究活跃对流云和风暴中的输送、扩散、冰的形成和冰雹胚胎的发展过程。科学目标将是增加对自然云和播种云中的这些过程及其与随后降水(包括冰雹)发展的关系的了解。主要的实验技术将使用从飞机上释放的示踪剂材料，包括气态SF6、雷达箔条和荧光珠(用于冰雹胚胎研究)。1993年的项目将侧重于示踪材料的脉冲释放(典型持续时间为30 S)，以便于研究运输和扩散过程以及水流星的时间演变。只要有机会，将在支线云中发布数据，以研究支线和主单元之间的传输，并在可用的其他云类型中进行研究。南达科他州矿业与技术学院T-28和北达科他州大学引文分校将对云中的SF6以及运动学和微物理特征进行采样。C波段多普勒雷达将提供降水来源的一次多普勒监测，并确定风暴是否具有支线单体特征。一个流动班级系统将提供对当地环境的及时探测。

The North Dakota Tracer Experiment planned for the summer of 1993 will focus on continued study of transport, dispersion, ice initiation, and hail embryo development processes in active convective clouds and storms. The scientific goal will be to increase understanding of these processes in natural and seeded clouds, and their relation to the subsequent development of precipitation (including hail). The primary experimental techniques will employ tracer materials released from aircraft, including gaseous SF6, radar chaff, and fluorescent beads (for hailstone-embryo studies). The 1993 project will emphasize pulsed releases (typical duration 30 s) of the tracer materials to facilitate studying the time evolution of transport and dispersion processes and of the hydrometeors. Releases will be made in feeder clouds whenever opportunities arise, to study transport between feeder and main cell, and in other cloud types as available. The South Dakota School of Mines and Technology T-28 and University of North Dakota Citation will sample the clouds for SF6 as well as for kinematic and microphysical characteristics. C-band Doppler radar will provide one Doppler surveillance of the origin of precipitation, and determine whether the storms have feeder cell characteristics. One mobile CLASS system will provide timely soundings of the local environment.