Lidar Measurements for Desert Dust Characterization: An Overview

Table 2

Synthesis of the most important measurement campaigns for dust characterization involving lidar measurements.

Measurement campaign	Location	Period	Main; references	Instruments	Lidar added value
INDOEX; (Indian Ocean Experiment); http://www-indoex.ucsd.edu/	Indian subcontinent; and Indian Ocean; (8°N–8°S, 70°E–80°E)	January–March 1999	[69, 158]	Ground-based: - Gas samplers/Proton Transfer Reaction; Mass  Spectrometer (PTR-MS)/Atmospheric Pressure  Chemical Ionization Mass Spectrometer  (AP-CIMS); - micro pulse lidar/multi-wavelength lidar	First vertical resolved; microphysical properties: 𝑟eff =0.20±0.08 𝜇m; SSA at 532 nm = 1–0.25; 𝐶𝑣 = 6–44 𝜇m^2/cm^3
PRIDE; (Puerto Rico Dust Experiment); http://modis-atmos.gsfc.nasa.gov/PRIDE	Puerto Rico; (18.21°N–65.60°W)	28 June–24 July 2000	[67, 159–161]	Ground-based; - surface station/2 AERONET  Sun-photometers/MICROTOPS sunphotometer; - micro pulse lidar; Airborne: - AATS-6 Sun-photometer/radiometers /2optical  counters; Research vessel: - in situ sensors	Highly variable layering: Dust up to 5 km; Dust intrusion in the; marine boundary layer
SHADE; (Saharan Dust Experiment)	Sal Island (Capo Verde); and M’Buor (Senegal)	9–29 September 2000	[68, 162]	Ground-based: - CIMEL Sun-photometers; Airborne: - in situ sensors/radiometers /POLDER  radiometer; -backscatter lidar	Lidar/in situ measurements integration; Dust in the PBL and up to 4.5 km; Smaller radius in the PBL
ACE-Asia; (Asian Pacific Regional Aerosol Characterization Experiment); http://saga.pmel.noaa.gov/aceasia	SE China, Korea, Japan; (22–50°N, 100–150°E)	Spring 2001	[163, 164]	Ground-based: - Backscatter/Raman lidars; - Sun photometer/Radiometers/Absorption  Photometer; Airborne: - AERONET Sun photometers/Radiometers/; PSAP/4 Nephelometer/In situ sensors; Shipborne: Micro pulse lidar; Spaceborne: - Aerosol and species retrievals	Depolarization measurements for discriminating spherical and no spherical particles; Dust extinction coefficient at 532 nm up to 0.3 km^−1
MINATROC; (Mineral dust and Tropospheric Chemistry)	Mount Cimone, Italy; (44.2°N, 10.7°E, 1870 m a.s.l.); Izana, Tenerife, Spain; (28.30°N, 16.48°W 2367 m asl)	June–July 2000; July –August 2002	[165]	- Differential mobility analyzer (DMA)/optical  particle counter (OPC); - Single backscatter depolarization lidar	Dust layering 2–8 km a.s.l.; Dust extinction coefficient 0.2 km^−1(532 nm); Particle linear depolarization ratio ~15% (532 nm)
CRYSTAL-FACE; (Cirrus Regional Study of Tropical Anvils and Cirrus Layers-Florida Area Cirrus); http://cloud1.arc.nasa.gov/crystalface	SW and SE Florida, USA; (24°–26°N 83°–80°W)	July 2002	[17, 166, 167]	Ground-based: - CIMEL Sun-photometers/Surface flux  measurements/UV/IR/Broadband radiometers; - Ceilometer; - Backscatter lidars; Airborne: - Sun-photometers/Radiometers/Nephelometer/In  situ sensors; Spaceborne: Aerosol and species retrievals	Dust particles are effective Ice Condensation Nuclei in mildly supercooled (−5.2/−8.8°C) altocumulus
UAE^2(Unified Aerosol Experiment); http://uae2.gsfc.nasa.gov/	United Arab Emirates, Arabian Gulf and Gulf of Oman.	August–September 2004	[168, 169]	Ground-based: - 15 sun-photometers/AERI interferometer/particle  sizer/NRL Mobile Atmospheric Aerosol And  Radiation Characterization (MAARCO)/NASA’s  Surface-sensing Measurements for Atmospheric  Radiative Transfer (SMART)/radiosonde; - Micro pulse lidars; Airborne: - Aerosol, clouds and water droplet probes/Cloud  Absorption Radiometer/Polar Nephelometer; - Lidar	Micro Pulse Lidar/Sun-photometer synergy: dust /clouds separation; AOD at 550 nm; AOD in IR in daytime; Large AOD variability; (range 0.4–0.53); Larger variability at coastal and island sites
AMMA; (African Monsoon Multidisciplinary Analysis); http://www.amma-international.org/spip.php?rubrique1	Africa (Mali-Niger-Nigeria-Senegal-Benin-Algeria, Mauritania); (8°–19°N, 2°–8°E)	2002–2010	[71, 170–172]	Ground-based: - SW-LW broadband  radiometers/AERONET/Microtops II  Sun-photometers/TEOMs/Particle/CCN  Counters/Aerosol filter sampling/Nephelometers/; Aethalometers/Pyranometers/Pyrgeometers/; Scatterometers/Pyrheliometers/Shadow band  radiometers/Gas samplers (O3, CO, SO2, NO𝑥, COV); - Ceilometers/Elastic/Raman  lidars/Depolarization/Raman lidars; Airborne: - PSAP-PMS- FFSSP/Nephelometer/Q-AMS/; Shortwave Spectrometer (SWS)/Eppley  radiometers/Solar Hemispheric Integrating; Measurement System (SHIMS)/Gas samplers; (O3, CO, SO2, NO𝑥)/Aerosol filter sampling	Mixing of dust with biomass burning particles (2–5 km); Dust extinction coefficient 0.2–0.4 km^−1, but also up to 1.5 km^−1 (355 nm); Particle linear depolarization ratio 25% (355 nm); 𝑆=55±5 sr^−1 (355 nm)
SAMUM -1; (Saharan Mineral Dust Experiment); http://samum.tropos.de/	South Morocco Ouarzazate; (30.9°N, 6.9°W, 1133 m a.s.l.); and Tinfou; (30.2°N, 5.6°W, 680 m asl)	May–June 2006	([175] and; references therein)	Ground-based: - in situ physical–chemical and optical  sensors/AERONET Sun-photometers/; Radiometers/Radiosonde/Surface-sensing  Measurements for Atmospheric Radiative  Transfer (SMART)/Compact radiation  measurement system (CORAS); - Raman lidars/Doppler lidar; Airborne: - in situ sensors; - HSRL	S (355 nm, 532 nm, 1064 nm) = 50–60 sr; Particle linear depolarization ratio: ~30% (532 nm); Å(𝛼) ~ 0; (355/532 nm); AOD < 0.8 (532 nm); Median effective diameter 2.5 𝜇m; CALIPSO underestimates the dust optical depth by about 25%.; Lidar-AERONET comparison: - Good agreement for pure dust  AOD and Å(𝛼).; -at near ultraviolet wavelengths  differences in complex refractive  index, lidar ratio and single  scattering albedo
SAMUM 2; (Saharan Mineral Dust Experiment); http://samum.tropos.de/	Cape Verde, Africa; ~15°N, 23.5°W	Winter 2008	[143, 155, 176]	Ground-based; - in situ physical–chemical and optical sensors/; 3 AERONET Sun-photometers/radiometers/1  radiosonde; - 3 Raman lidars/1 Doppler lidar; Airborne; - in situ sensors; - HSRL	Dust layers depth (1.3±0.4 km); Dust S (355 nm, 532 nm, 1064 nm): 50–60 sr; Dust particles significantly aged