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).
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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).