| Volumes and Issues Contents of Issue 4 |
www.atmos-meas-tech-discuss.net/3/3907/2010/
doi:10.5194/amtd-3-3907-2010
© Author(s) 2010. This work is distributed
under the Creative Commons Attribution 3.0 License.
Ceilometer-lidar inter-comparison: backscatter coefficient retrieval and signal-to-noise ratio determination
1Leibniz-Institute for Tropospheric Research, Permoserstr. 15, 04318 Leipzig, Germany
2German Meteorological Service, Meteorological Observatory Hohenpeissenberg, Germany
3JENOPTIK, ESW GmbH, Jena, Germany
Abstract. The potential of a new generation of ceilometer instruments for aerosol monitoring has been studied in the Ceilometer-Lidar Inter- Comparison (CLIC) study. The ceilometer is of type CHM15k from Jenoptik, Germany, which uses a solid state laser at the wavelength of 1064 nm and an avalanche photodiode for photon counting detection. The German Meteorological Service is in progress of setting up a ceilometer network for aerosol monitoring in Germany. The intercomparison study was performed to determine whether the ceilometers are capable to deliver quality assured particle backscatter coefficient profiles. For this, the derived ceilometer profiles were compared to simultaneously measured lidar profiles at the same wavelength. The lidar used for this intercomparison was IfTs multi-wavelengths Raman lidar PollyXT. During the EARLINET lidar intercomparison campaign EARLI 09 in Leipzig, Germany, a new type of the Jenoptik ceilometer, the CHM15k-X, took part. This new ceilometer has a new optical setup resulting in a complete overlap at 150 m. The derived particle backscatter profiles were compared to profiles derived from PollyXTs measurements, too. The elastic daytime particle backscatter profiles as well as the less noisy night-time Raman particle backscatter profiles compare well with the ceilometers profiles in atmospheric structures like aerosol layers or the boundary layer top height. The calibration of the ceilometer profiles by an independent measurement of the aerosol optical depth (AOD) by a sun photometer is necessary to determine the correct magnitude of the particle backscatter coefficient profiles. A comprehensive signal-to-noise ratio study was carried out to characterize the ceilometers signal performance with increasing altitude.
Discussion Paper (PDF, 821 KB) Interactive Discussion (Closed, 6 Comments) Final Revised Paper (AMT)
Notice on Discussion StatusCitation: Heese, B., Flentje, H., Althausen, D., Ansmann, A., and Frey, S.: Ceilometer-lidar inter-comparison: backscatter coefficient retrieval and signal-to-noise ratio determination, Atmos. Meas. Tech. Discuss., 3, 3907-3924, doi:10.5194/amtd-3-3907-2010, 2010. Bibtex EndNote Reference Manager XML
