Chinese researchers have improved the accuracy of short-term forecasts for convective rainfall using lightning data.
Lightning is the result of strong convection. It can effectively indicate the upward motion and the microphysical processes of cold clouds in thunderstorms.
Lightning detection and location technology have witnessed rapid development in recent years. At present, the 3D lightning mapping technology has reduced the lightning horizontal location error to meters.
In order to obtain reliable lightning location data and promote the application of lightning in improving short and imminent precipitation forecast, the researchers from the Institute of Atmospheric Physics, Chinese Academy of Sciences (CAS), have conducted field campaigns in warm seasons for consecutive years and learned the characteristics and patterns of high-impact weather systems in Beijing and its surrounding areas.
They studied the relation between lightning and the microphysical characteristics such as ice and water substance content.
Based on the physical connection between lightning and strong ascending motion within the cloud, the researchers extracted the observation information of convective dynamic field and realized the assimilation of lightning data.
The lightning data assimilation is expected to offer more small-scale convective information in remote areas without enough radar data, and hence enhance the accuracy of local rainfall forecast, according to the CAS.