Flash floods are major meteorological disasters which occur around the globe. Understanding of this phenomena is a challenging problem because it is necessary to understand both complex dynamic and microphysical processes at scales of motion that are smaller than typically measured by conventional weather networks. This scale of motion is termed mesoscale by meteorologists. The National Science Council of Taiwan has established a Multiple Hazards Mitigation Project whose meteorological component is focussed on improving flash flood predictions. A major field project to study the systems that cause flash floods, entitled the Taiwan Area Mesoscale Experiment, was held in the Spring of 1987. The project was cosponsored by the National Science Council with participation of the National Science Foundation and the National Oceanic and Atmospheric Administration of the United States. The Principal Investigator participated in the field expedition and his preliminary research on the data has revealed the structure of subtropical mesoscale convective systems and the differences and similarities with mid-latitude systems. Such comparisons have not received much attention in the past. The Principal Investigator will continue this research with special attention to comparing the dynamic and thermodynamic characteristics of two convective systems that possessed very different precipitation characteristics.
