New Ceilometer for High Range Cloud Detection  

Vaisala (Finland) introduces a new cloud height detector, the Vaisala Ceilometer CL51 at the American Meteorological Society’s Annual Meeting. The CL51 is designed to measure cloud base height and vertical visibility in all weather conditions, which makes it an ideal instrument for meteorological applications that rely on reliable cloud height detection.

When combined with new application software also developed by Vaisala, the CL51 reports planetary boundary layer structure parameters like mixing layer height and residual layer height. This means that the CL51 can be used to measure and forecast air quality. All data can be exported from the software for advanced analysis and research purposes.

The CL51 utilizes advanced optical single lens technology for high range measurement, which makes its performance during precipitation and low cloud conditions unsurpassed. Thanks to the strong and stable signal over the whole measurement range that the single lens technology enables, the CL51 reports high altitude cirrus clouds without unsurpassing the low and middle layer clouds, or vertical visibility in harsh conditions.

CL51 is able to detect three cloud layers simultaneously throughout a measurement range that extends from ground level to 43,000 feet (13 kilometers). It employs a pulsed diode laser LIDAR (Light Detection And Ranging) technology, where short laser pulses are sent out, and the reflection of light caused by clouds, precipitation or other obscuration is used to determine cloud base height.