A few Applications of Airborne Lidar for Space Science
Marenco, Franco1; Cooke, Michael1; Francis, Peter1; Newman, Stuart1; Amiridis, Vassilsi2; Marinou, Eleni2; Tsekeri, Alexandra2; Marsham, John3
1Met Office, UNITED KINGDOM; 2National Observatory of Athens, GREECE; 3University of Leeds, UNITED KINGDOM

Since 2009, the Facility for Airborne Atmospheric Measurements BAe-146 atmospheric research aircraft (FAAM, www.faam.ac.uk) is equipped with a cloud/aerosol lidar. Having a lidar on an airborne platform has the unique advantage of being able to take it to different observation scenes around the world, based on scientific requirements. Moreover, a fully instrumented platform such as the BAe-146 permits complementing the lidar observations with several other on-board sensors, both remote sensing and in situ. In this talk, we shall describe a few of the applications of the airborne lidar: (a) During the eruption of Eyjafjallajokull in 2010, a detailed dataset of volcanic ash concentrations has been compiled during six research flights over the United Kingdom and surrounding seas (Marenco et al, 2011). This dataset has been successfully used for the improvement of dispersion models and for the validation of satellite products based on IASI and SEVIRI (see e.g. Francis et al, 2012). Fig. 1 illustrates an example of a direct comparison of volcanic ash column loadings derived by SEVIRI and the airborne lidar. (b) Underpasses of the CALIPSO satellite have been performed, for the evaluation of its products in terms of aerosol subtype and extinction coefficient. Two flights will be discussed in detail. The first one was carried out over the city of Thessaloniki on 9 September 2011 (Amiridis et al, 2012) during ACEMED; and the second flight (20 September 2012) took place in the Amazon forest in the biomass burning season (SAMBBA campaign). Difficulties with the CALIPSO automated retrievals have been highlighted, in terms of cloud filtering and aerosol subtyping, but vertical profiles averaged over a large horizontal distance tend to show a good agreement. Fig. 2 illustrates the comparison for the 2011 case study. (c) Several research flights have taken place over the Sahara in 2011 and 2012 within the Fennec campaign, in an environment where elevated optically thick dust layers are frequently capped by liquid or mixed phase clouds (Ryder et al, 2013). Two on-board remote sensing instruments can be used to set up an automated cloud-detection algorithm and distinguish clouds from dust: the lidar and the ARIES infrared interferometer. We shall discuss how combining these datasets may help validating cloud detection from SEVIRI in this remote area of the world. *** Acknowledgments: *** Airborne data was obtained using the BAe-146-301 Atmospheric Research Aircraft (ARA) flown by Directflight Ltd. and managed by the Facility for Airborne Atmospheric Measurements (FAAM), which a joint entity of the Natural Environment Research Council (NERC) and the Met Office. The ACEMED research has received funding from EUFAR (EC FP7/2007-2013 grant n. 227159). Fennec was funded by NERC (grant NE/G017166/). *** References: *** Amiridis, V., A. Tsekeri, F. Marenco, E. Marinou, E. Giannakaki, D. Balis, A. Nenes, Validation of CALIPSO nighttime aerosol products using airborne lidar and in-situ observations, 26th International Laser Radar Conference, Porto Heli, Greece (2012). Francis, P.N., M.C. Cooke, and R.W. Saunders, Retrieval of physical properties of volcanic ash using Meteosat: A case study from the 2010 Eyjafjallajokull eruption, J. Geophys. Res., 117, D00U09, doi:10.1029/2011JD016788 (2012). Marenco, F., B.T. Johnson, K.F. Turnbull, S. Newman, J.M. Haywood, H. Webster, and H. Ricketts, Airborne lidar observations of the 2010 Eyjafjallajokull volcanic ash plume, J. Geophys. Res. 116, D00U05, doi:10.1029/2011JD016396 (2011). Ryder, C.L., E.J. Highwood, P.D. Rosenberg, J. Trembath, J.K. Brooke, M. Bart, A. Dean, J. Crosier, J. Dorsey, H. Brindley, J. Banks, J.H. Marsham, J.B. McQuaid, H. Sodemann, and R. Washington, Optical properties of Saharan dust aerosol and contribution from the coarse mode as measured during the Fennec 2011 aircraft campaign, Atmos. Chem. Phys., 13, 303-325 (2013).