Lightning is a natural phenomenon that has much impact on man and man-made systems. Lightning can be generally characterized as either negative return stroke (NRS) or positive return stroke (PRS). PRS have high peak currents and long continuing current that are responsible for more intense damage than negative return strokes. However, PRS are considerably less studied compared to NRS due the complexity and paucity of PRS. This study attempts to provide an overview of the positive lightning characteristic research in recent years. The review is classified into four groups, which are: preliminary breakdown pulse of positive lightning, compact intracloud discharge, positive leader and positive lightning return stroke. In spite of recent progress made in this area, our knowledge on the physics of positive lightning remains considerably poorer than negative lightning. Many questions regarding the characteristic of positive lightning and their properties cannot be answered without further research. It would be of great interest to examine the positive lightning parameters under different meteorological conditions as well.
展开▼
