Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
doi:10.5194/acp-2017-240
© Author(s) 2017. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
13 Apr 2017
Review status
This discussion paper is under review for the journal Atmospheric Chemistry and Physics (ACP).
Impact of aerosol hygroscopic growth on retrieving aerosol extinction coefficient profiles from elastic-backscatter lidar signals
Gang Zhao1, Chunsheng Zhao1, Ye Kuang1, Jiangchuan Tao1, Wangshu Tan1, Yuxuan Bian2, Jing Li1, and Chengcai Li1 1Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, China
2State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing, 100081, China
Abstract. Light detection and ranging (lidar) measurements have been widely used to profile ambient aerosol extinction coefficient (σext). Particle extinction-to-backscatter ratio (lidar ratio, LR), which highly depends on aerosol dry particle number size distribution (PNSD) and aerosol hygroscopicity, is introduced to retrieve the σext profile from elastic-backscatter lidar signals. Conventionally, a constant column integrated LR that is estimated from aerosol optical depth is used by the retrieving algorithms. In this paper, the influences of aerosol PNSD, aerosol hygroscopic growth and relative humidity (RH) profiles on the variation of LR are investigated based on the datasets from field measurements in the North China Plain (NCP). Results show that LR has an enhancement factor of 2.2 when RH reaches 92 %. Simulation results indicate that both the magnitude and vertical structures of the σext profiles by using column-related LR method are significantly biased from the original σext profile. The relative bias, which is mainly influenced by RH and PNSD, can reach up to 40 % when RH at the top of the mixed layer is above 90 %. A new algorithm for retrieving σext profiles and a new scheme of LR enhancement factor by RH in the NCP are proposed in this study. The relative bias between the σext profile retrieved with this new algorithm and the ideal true value is reduced to below 13 %.

Citation: Zhao, G., Zhao, C., Kuang, Y., Tao, J., Tan, W., Bian, Y., Li, J., and Li, C.: Impact of aerosol hygroscopic growth on retrieving aerosol extinction coefficient profiles from elastic-backscatter lidar signals, Atmos. Chem. Phys. Discuss., doi:10.5194/acp-2017-240, in review, 2017.
Gang Zhao et al.
Gang Zhao et al.
Gang Zhao et al.

Viewed

Total article views: 501 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
389 91 21 501 4 24

Views and downloads (calculated since 13 Apr 2017)

Cumulative views and downloads (calculated since 13 Apr 2017)

Viewed (geographical distribution)

Total article views: 501 (including HTML, PDF, and XML)

Thereof 495 with geography defined and 6 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 27 May 2017
Publications Copernicus
Download
Short summary
In this paper, influences of aerosol hygroscopic growth on lidar ratio are studied. Results indicate that both the magnitude and vertical structures of the retrieved aerosol extinction coefficient (σext) profile from lidar signals are significantly biased. This study proposed a feasible method of reducing the bias of retrieving σext profile and this method can be implemented in operational retrieval of aerosol σext profile and pollution monitoring.
In this paper, influences of aerosol hygroscopic growth on lidar ratio are studied. Results...
Share