ALCF

Automatic Lidar and Ceilometer
Framework

Documentation

Supported ALCs

The following ALCs are supported:

Vaisala CL31, CL51, CL61

Type: blview, cl31, cl51, cl61

Vaisala CL31, CL51 and CL61 are ceilometers which use near-infrared wavelength of 910 nm. CL31 and CL51 store backscatter in DAT files. These can be converted to NetCDF with the alcf convert cl51 <input> <output> command, where <input> and <output> are input and output directories, respectively. CL61 produces native NetCDF files. The converted and native “L2” NetCDF files can be used as input to the alcf auto lidar and alcf lidar commands. Alternatively, you can use the tool cl2nc to convert the CL31 and CL51 DAT files to NetCDF.

The types cl31, cl51 read NetCDF files produced by cl2nc (or alcf convert cl51 <input> <output>). The type cl61 reads native NetCDF files produced by the CL61 instrument. The type blview reads L2 NetCDF produced by the vendor software BL-VIEW.

The 910-nm wavelength band used by CL31, CL51 and CL61 is affected by water vapour absorption lines (Wiegner et al., 2019). The ALCF currently does not support simulating water vapour absorption, and it is not taken into account in the calibration process.

Sigma Space MiniMPL

Type: mpl (mpl2nc)

Sigma Space MiniMPL is a lidar which use visible wavelength of 532 nm. The instrument stores backscatter in MPL files. These can be converted to NetCDF using the SigmaMPL software. The NetCDF files can then be used as input to the alcf auto lidar and alcf lidar commands. The tool mpl2nc can also convert MPL files to NetCDF. Use the lidar type mpl2nc with alcf auto lidar and alcf lidar to process data from mpl2nc.

Lufft CHM 15k

Type: chm15k

Lufft CHM 15k is a ceilometer which uses near-infrared wavelength of 1064 nm. The instrument stores backscatter in NetCDF files, which can be used directly with the ALCF commands alcf auto lidar and alcf lidar without conversion.

CALIPSO/CALIOP

Type: caliop

CALIOP is a spaceborne lidar on board of the CNES-NASA satellite CALIPSO. The ALCF supports lidar simulation of a spaceborne lidar at 532 nm, i.e. it can produce simulated backscatter profiles from atmospheric model data. Therefore, this lidar type can be used with alcf simulate and alcf auto model, but not with alcf lidar or alcf auto lidar.