Atmospheric Radiation Measurement Climate Research Facility US Department of Energy

hsrlcfad > CFADs calculated using ARM HSRL measurements and lidar scattering ratio methodVAP Type(s) > Evaluation

To facilitate the direct comparison of climate model outputs with its ground-based lidar measurements, ARM provides joint histograms of the lidar scattering ratio frequency distribution at each height. Scientists can compare these joint histograms, also called contoured frequency altitude diagrams (CFADs), with outputs from lidar simulators such as the Earth Model Column Collaboratory (EMC2) and version 2 of the Cloud Feedbacks Model Intercomparison Project (CFMIP) Observation Simulator Package (COSP2.0). This data set contains vertically regridded lidar scattering ratio and joint histograms of the scattering ratio and height up to 20,000 meters, and it is generated using measurements from the high-spectral-resolution lidar.

The joint histograms are created for every hour with a 100-meter vertical resolution to capture both the diurnal variability of clouds and their fine vertical structures.

Primary Derived Measurements


  • Fixed
  • AMF1
  • AMF2
  • AMF3