Vaisala CL51 Lidar Ceilometer

The MAPNet facilities use two identical Vaisala CL51 lidar ceilometers. These ceilometers provide a measure of attenuated volume backscatter at 10-meter vertical resolution from 10 meters to 15 km AGL. Provided data include range-normalized backscatter and cloud base height (up to 3 layers) and is averaged over 15 second intervals. At 910 nm, these lidars are not only used for cloud property detection, but they are also sensitive to aerosol scattering which can provide estimates of mixed layer heights and aerosol depth information. The CL51s is a monostatic system (one lens that is used for both transmitting and receiving) and uses a pulsed laser that is backscattered off aerosols and clouds to the receiver.

The MIPS ceilometer

  • Wavelength: 910 nm
  • Measurement Range: 0-15km
  • Gate Spacing: 10 m
  • Detectable Layers: 3
  • Time Resolution: Adjustable (Currently 15 seconds)
  • Peak Power: 27 W
  • Beam Divergence: 0.15 mrad

Ceilometer data showing aerosols in the boundary layer (BL) at night and a building convective BL throughout the day.

The MIPS Ceilometer sees smoke from local fires at night.