Share Email Print
cover

Proceedings Paper

Aerosol concentration measurements with a lidar ceilometer: results of a one year measuring campaign
Author(s): Christoph Muenkel; Stefan Emeis; Wolfgang J. Mueller; Klaus P. Schaefer
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

The Vaisala ceilometer CT25K is an eye-safe commercial lidar mainly used to report cloud base heights and vertical visibility for aviation safety purposes. Compared to ceilometers with biaxial optics, its single lens design provides a higher signal-to-noise ratio for lidar return signals from distances below about 600 m, thus increasing its abilities to examine the mixing layer. A CT25K ceilometer took part in the environmental research project VALIUM at the Lower Saxony State Agency for Ecology (NLO) in Hannover, Germany, investigating the air pollution in an urban surrounding with various sensors. Lidar return signals are reported every 15 s with a height resolution of 15 m. This paper covers two aspects of the interpretation of these signals. The aerosol backscatter of the atmosphere up to 30 m is compared to the PM10 concentration reported by an in situ sensor every 30 minutes, and the results are interpreted in respect of meteorological parameters such as humidity, temperature, wind, and global radiation. With relative humidity values below 62 % and no rain present the correlation between ceilometer backscatter and PM10 values is good enough to qualify standard ceilometers as instruments for a quantitative analysis of the atmospheric aerosol contents. Backscatter values up to 1000 m height are presented that allow an estimation of the convective boundary layer top in dry weather situations. The atmospheric boundary layer structures derived from ceilometer data are compared to those reported by a SODAR and a RASS that also took part in the VALIUM research project. Finally the backscatter data quality of a double lens ceilometer is compared to that of the single lens CT25K ceilometer to investigate to what extent these lidar systems are also able to report aerosol concentration.

Paper Details

Date Published: 16 February 2004
PDF: 11 pages
Proc. SPIE 5235, Remote Sensing of Clouds and the Atmosphere VIII, (16 February 2004); doi: 10.1117/12.511104
Show Author Affiliations
Christoph Muenkel, Vaisala GmbH (Germany)
Stefan Emeis, Forschungszentrum Karlsruhe (Germany)
Wolfgang J. Mueller, Niedersachsisches Landesamt fuer Oekologie (Germany)
Klaus P. Schaefer, Forschungszentrum Karlsruhe (Germany)


Published in SPIE Proceedings Vol. 5235:
Remote Sensing of Clouds and the Atmosphere VIII
Klaus P. Schaefer; Adolfo Comeron; Michel R. Carleer; Richard H. Picard, Editor(s)

© SPIE. Terms of Use
Back to Top