可以测量各种类型的 降水,包括雨、雨夹 雪、冰雹、雪、混合 降水和大雾的精确量 值和形态及速度。 通过对空气中粒子的 种类、大小、速度指 标的测量,分析给当 前天气现象实况。尤 其适合交通领域的天 气现象的实况监测和 预警。 46 The Vaisala Present Weather Detector PWD22. 47 Vaisala Weather Sensor FD12P The surface of the capacitive precipitation sensor "feels" the amount of water that falls on it. When frozen precipitation collects on the surface it is heated in a carefully controlled manner. The resulting water is measured to find the water equivalent of the frozen precipitation. 48 4 天气现象 1. 雨