Relative humidity vertical profiling using lidar-based synergistic methods in the framework of the hygra-cd campaign

Relative humidity vertical profiling using lidar-based synergistic methods in the framework of the hygra-cd campaign

Labzovskii, Lev D. (Southern University of Science and Technology of China)
Papayannis, Alexandros (National Technical University of Athens)
Binietoglou, Ioannis (National Institute of RandD for Optoelectronics; Raymterics S.A.)
Banks, R.F. (TU Delft Atmospheric Remote Sensing; Barcelona Supercomputing Center (BSC))
Baldasano, Jose M. (Barcelona Supercomputing Center (BSC); Universitat Politecnica de Catalunya)
Toanca, Florica (National Institute of RandD for Optoelectronics)
Tzanis, Chris G. (National and Capodistrian University of Athens)
Christodoulakis, John (National and Capodistrian University of Athens)

2018-02-14

Accurate continuous measurements of relative humidity (RH) vertical profiles in the lower troposphere have become a significant scientific challenge. In recent years a synergy of various ground-based remote sensing instruments have been successfully used for RH vertical profiling, which has resulted in the improvement of spatial resolution and, in some cases, of the accuracy of the measurement. Some studies have also suggested the use of high-resolution model simulations as input datasets into RH vertical profiling techniques. In this paper we apply two synergetic methods for RH profiling, including the synergy of lidar with a microwave radiometer and high-resolution atmospheric modeling. The two methods are employed for RH retrieval between 100 and 6000ĝ€m with increased spatial resolution, based on datasets from the HygrA-CD (Hygroscopic Aerosols to Cloud Droplets) campaign conducted in Athens, Greece from May to June 2014. RH profiles from synergetic methods are then compared with those retrieved using single instruments or as simulated by high-resolution models. Our proposed technique for RH profiling provides improved statistical agreement with reference to radiosoundings by 27ĝ€% when the lidar-radiometer (in comparison with radiometer measurements) approach is used and by 15ĝ€% when a lidar model is used (in comparison with WRF-model simulations). Mean uncertainty of RH due to temperature bias in RH profiling was ĝ1/4 4.34ĝ€% for the lidar-radiometer and ĝ1/4 1.22ĝ€% for the lidar-model methods. However, maximum uncertainty in RH retrievals due to temperature bias showed that lidar-model method is more reliable at heights greater than 2000ĝ€m. Overall, our results have demonstrated the capability of both combined methods for daytime measurements in heights between 100 and 6000ĝ€m when lidar-radiometer or lidar-WRF combined datasets are available.

Atmospheric composition and structure (instruments and techniques)

http://resolver.tudelft.nl/uuid:c145380e-436c-4fe4-be7f-f44410f31384

https://doi.org/10.5194/angeo-36-213-2018

0992-7689

Annales Geophysicae: atmospheres, hydrospheres and space sciences, 36 (1), 213-229

Institutional Repository

journal article

© 2018 Lev D. Labzovskii, Alexandros Papayannis, Ioannis Binietoglou, R.F. Banks, Jose M. Baldasano, Florica Toanca, Chris G. Tzanis, John Christodoulakis