Articles | Volume 9, issue 3
Atmos. Meas. Tech., 9, 1113–1133, 2016

Special issue: EARLINET, the European Aerosol Research Lidar Network

Atmos. Meas. Tech., 9, 1113–1133, 2016

Research article 18 Mar 2016

Research article | 18 Mar 2016

A comparative study of aerosol microphysical properties retrieved from ground-based remote sensing and aircraft in situ measurements during a Saharan dust event

María José Granados-Muñoz1,2,a, Juan Antonio Bravo-Aranda1,2, Darrel Baumgardner3, Juan Luis Guerrero-Rascado1,2, Daniel Pérez-Ramírez4,5, Francisco Navas-Guzmán6, Igor Veselovskii7, Hassan Lyamani1,2, Antonio Valenzuela1,2, Francisco José Olmo1,2, Gloria Titos1,2, Javier Andrey8,b, Anatoli Chaikovsky9, Oleg Dubovik10, Manuel Gil-Ojeda8, and Lucas Alados-Arboledas1,2 María José Granados-Muñoz et al.
  • 1Andalusian Institute for Earth System Research (IISTA-CEAMA), Avd. del Mediterráneo, 18006, Granada, Spain
  • 2Dpt. Applied Physics, University of Granada, Fuentenueva s/n, 18071, Granada, Spain
  • 3Droplet Measurement Technologies, Boulder, CO 80301, USA
  • 4Mesoscale Atmospheric Processes Laboratory, NASA Goddard Space Flight Center, 20771, Greenbelt, Maryland, USA
  • 5Universities Space Research Association, 21044, Columbia, Maryland, USA
  • 6Institute of Applied Physics (IAP), University of Bern, Bern, Switzerland
  • 7Physics Instrumentation Center of General Physics Institute, Troitsk, Moscow Region, 142190, Russia
  • 8Instituto Nacional de Técnica Aeroespacial (INTA), Ctra. Ajalvir km. 4, 28850 Torrejón de Ardoz, Spain
  • 9Institute of Physics, National Academy of Science, Minsk, Belarus
  • 10Laboratoire d'Optique Atmospherique, CNRS Universite de Lille 1, Bat P5 Cite scientifique, 59655 Villeneuve d'Ascq CEDEX, France
  • acurrently at: Table Mountain Facility, NASA/Jet Propulsion Laboratory, California, Institute of Technology, Wrightwood, California, USA
  • bcurrently at: CNRM-GAME, Météo-France, Tolouse, France

Abstract. In this work we present an analysis of aerosol microphysical properties during a mineral dust event taking advantage of the combination of different state-of-the-art retrieval techniques applied to active and passive remote sensing measurements and the evaluation of some of those techniques using independent data acquired from in situ aircraft measurements. Data were collected in a field campaign performed during a mineral dust outbreak at the Granada, Spain, experimental site (37.16° N, 3.61° W, 680 m a.s.l.) on 27 June 2011. Column-integrated properties are provided by sun- and star-photometry, which allows for a continuous evaluation of the mineral dust optical properties during both day and nighttime. Both the linear estimation and AERONET (Aerosol Robotic Network) inversion algorithms are applied for the retrieval of the column-integrated microphysical particle properties. In addition, vertically resolved microphysical properties are obtained from a multi-wavelength Raman lidar system included in EARLINET (European Aerosol Research Lidar Network), by using both LIRIC (Lidar Radiometer Inversion Code) algorithm during daytime and an algorithm applied to the Raman measurements based on the regularization technique during nighttime. LIRIC retrievals reveal the presence of dust layers between 3 and 5 km a.s.l. with volume concentrations of the coarse spheroid mode up to 60 µm3 cm−3. The combined use of the regularization and LIRIC methods reveals the night-to-day evolution of the vertical structure of the mineral dust microphysical properties and offers complementary information to that from column-integrated variables retrieved from passive remote sensing. Additionally, lidar depolarization profiles and LIRIC retrieved volume concentration are compared with aircraft in situ measurements. This study presents for the first time a comparison of the total volume concentration retrieved with LIRIC with independent in situ measurements, obtaining agreement within the estimated uncertainties for both methods and quite good agreement for the vertical distribution of the aerosol layers. Regarding the depolarization, the first published data set of the CAS-POL for polarization ratios is presented here and qualitatively compared with the lidar technique.

Short summary
A Saharan dust event is studied in detail using ground-based remote sensing measurements from lidar technology, as well as sun- and star-photometers. The use of combined techniques allows for obtaining both profiles and column-integrated microphysical properties during night and daytime. Besides, for the first time a validation of the CAS-POL depolarization measurements and LIRIC profiles is performed, thanks to the availability of aircraft in situ measurements, obtaining reasonable agreement.