Observation of vertical wind by in-situ and remote sensing systems

Vertical air speed plays an important role in several atmospheric processes e.g. like in turbulent transport and cloud formation. During the IMPACT campaign in May 2008 at Cabauw, the Netherlands, several systems were operated capable of sensing the vertical air speed with moderate to high temporal resolution [1]. Amongst these systems were 1) sonic anemometers mounted in a 200 m high meteorological tower, 2) a 1.55 μm Doppler wind lidar, and 3) a 35 GHz cloudradar. The Doppler lidar was operated during the campaign for a period of 7 days only. During this period some interesting cases for intercomparison were observed.
The sonic anemometer has the highest sampling rate. The data used here have a temporal resolution of 0.1 s. The Doppler lidar tracks mainly aerosols with diameter larger than 500 nm. The default operational mode of the lidar has a vertical resolution of 50 m, a time resolution of 10 s and the first gate at 100 m agl. The Doppler cloudradar typical measures the speed of cloud droplets and particulate matter suspended in air with a time resolution of approximately 15 s and vertical resolution of 90 m.
Here we focus on the vertical speed measured by these three systems on the 23rd of May 2008.