Urban Boundary Layer Measurements with a Commercial Ceilometer

Vaisala CT25K ceilometer is an eye-safe backscatter lidar particularly designed for cloud base detection. Due to the low laser power used, detecting the boundary layer aerosols offers a technological challenge.

Thanks to the single-lens optical design, the CT25K is capable of measuring backscatter accurately also from very low altitudes. Suitably processed, the time series of backscatter profiles gives insight into the evolution of the boundary layer in urban environment and provides a potential basis for continuous boundary layer observation. Measured data sets are used for evaluating the performance under different meteorological conditions. The limiting factors and conditions concerning the estimation of boundary layer depth will be discussed.