LICHT#

LICHT Raman Lidar, 3D drawing LICHT Raman Lidar at BCO at night

The Raman lidar system LICHT (LIdar for Cloud, Humidity and Temperature profiling) was designed and built in 2013 to expand the observation capability of MPI-M and in particular to be replacement system for EARLI lidar deployed at that moment at the BCO station. The LICHT lidar has similar measurement characteristics to EARLI and was already designed for high isolation from the outdoor environment. Besides better protection against a harsh environment, the LICHT lidar is capable of obtaining daytime water vapor measurements. Operation range for LICHT was extended from 15 km to 29 km on June 14, 2017. In addition, LICHT is equipped with automated window washing installation (built in and activated on July 7, 2017) that allows significant improvement of data quality thanks to reduced transmission losses on output and input windows of lidar container. The LICHT lidar system was deployed at BCO from July 2016 until December 2019. The LICHT lidar operated on board of the German research vessel Meteor during the EUREC4A campaign (January to February, 2020).

In 2026, we will remove CORAL for maintenance and reinstall LICHT at the BCO… more from this instrument soon!

Configurations#

The same information about resolution, smoothing, and calibration modes from coral apply here, but LICHT has also been operated with two height range configurations: 20 m to 15 km (1) and 20 m to 29 km (2).

  • 2min timestep, 118min temperature smoothing, 20m-15km range from 2016-07-17 until 2017-06-13 available as BCO.lidar_LICHT_LR_t_c1_v1 and BCO.lidar_LICHT_LR_b_c1_v1

  • 2min timestep, 118min temperature smoothing, 20m-29km range from 2017-06-17 until 2019-12-06 available as BCO.lidar_LICHT_LR_t_c2_v1 and BCO.lidar_LICHT_LR_b_c2_v1

Current data availability#

Data is available as .zarr files in the catalog as follows:

Dataset name

Temporal resolution

Smoothing

Water vapor calibration

Start date

End date

BCO.lidar_LICHT_lr_f_reanalysis_c1_v1

2 min

2 min

3D prior & future

2016-07-17

2017-06-13

BCO.lidar_LICHT_lr_s_reanalysis_c1_v1

2 min

??

3D prior & future

2016-07-17

2017-06-13

BCO.lidar_LICHT_lr_s_reanalysis_c2_v1

2 min

??

3D prior & future

2017-06-17

2019-12-06

BCO.lidar_LICHT_lr_f_reanalysis_c2_v1

2 min

2 min

3D prior & future

2017-06-17

2019-12-06

BCO.lidar_LICHT_lr_f_rolling_c1_v1

2 min

2 min

3D prior

2016-07-17

2017-06-13

BCO.lidar_LICHT_lr_s_rolling_c1_v1

2 min

??

3D prior

2016-07-17

2017-06-13

BCO.lidar_LICHT_lr_s_rolling_c2_v1

2 min

??

3D prior

2017-06-17

2019-12-06

BCO.lidar_LICHT_lr_f_rolling_c2_v1

2 min

2 min

3D prior

2017-06-17

2019-12-06

Calibration constants are written to the catalog as well, as .zarr under BCO.lidar_LICHT_calib_v1.

Data access#

The fast and slow smoothed products create datasets that differ as shown below:

import intake

cat = intake.open_catalog("https://tcodata.mpimet.mpg.de/catalog.yaml")
#fast = cat.BCO.lidar_LICHT_lr_f_rolling_c1_v1.to_dask()
#slow = cat.BCO.lidar_LICHT_lr_s_rolling_c1_v1.to_dask()
# plot range averaging windows and use datasets to dynamically generate useful docs info?
#fast
#slow

On board METEOR#

For the deployments on board the METEOR ship, please have a look at the METEOR page.