New laser technology to determine present weather parameters

Abstract

Present weather sensors are becoming increasingly important as a means to\naugment networks of automated weather stations and extend the capability\nof manned observations. The classification of hydrometeors is one of the\nprincipal tasks that is addressed by present weather sensors. In this paper,\nwe discuss a new laser-based technology for this purpose. The system\nimproves upon current precipitation monitors by using a derivative of phase\nDoppler anemometry techniques to accurately determine particle speed and\nsize. The instrument is also capable of distinguishing between liquid\ndroplets and solid polycrystalline hydrometeors and can be used to estimate\nvisibility. The incorporation of this technology into a meteorological station\nwith other sensors, such as temperature and relative humidity probes, leads\nto the accurate classification of particle type. The example data shown are\ntaken from tests in Leicestershire, England and Utah, USA and show the\ndifferences between solid and liquid precipitation events.