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G. Pappalardo,
L. Mona,
G. D'Amico,
U. Wandinger,
M. Adam,
A. Amodeo,
A. Ansmann,
A. Apituley,
L. Alados Arboledas,
D. Balis, [......],
M. Sicard,
V. Simeonov,
N. Spinelli,
K. Stebel,
M. Tesche,
T. Trickl,
X. Wang,
F. Wagner,
M. Wiegner,
K.M. Wilson
Atmospheric Chemistry and Physics 01/2013;
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G Pappalardo,
L Mona,
G D'Amico,
U Wandinger,
M Adam,
A Amodeo,
A Ansmann,
A Apituley,
L Alados Arboledas,
D Balis, [......],
M Sicard,
V Simeonov,
N Spinelli,
K Stebel,
M Tesche,
T Trickl,
X Wang,
F Wagner,
M Wiegner,
K M Wilson
Atmospheric Chemistry and Physics Discussions. 01/2012; 12(11):30203-30257.
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D. MÜLLER,
B. HEINOLD,
M. TESCHE,
I. TEGEN,
D. ALTHAUSEN,
L. ALADOS ARBOLEDAS,
V. AMIRIDIS,
A. AMODEO,
A. ANSMANN,
D. BALIS, [......],
L. MONA,
A. PAPAYANNIS,
G. PAPPALARDO,
R.-M. PERRONE, G. PISANI,
V. RIZI,
M. SICARD,
N. SPINELLI,
A. TAFURO,
M. WIEGNER
[show abstract]
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ABSTRACT: We observed a long-range transport event of mineral dust from North Africa to South Europe during the Saharan Mineral Dust Experiment (SAMUM) 2006. Geometrical and optical properties of that dust plume were determined with Sun photometer of the Aerosol Robotic Network (AERONET) and Raman lidar near the North African source region, and with Sun photometers of AERONET and lidars of the European Aerosol Research Lidar Network (EARLINET) in the far field in Europe. Extinction-to-backscatter ratios of the dust plume over Morocco and Southern Europe do not differ. Ångström exponents increase with distance from Morocco. We simulated the transport, and geometrical and optical properties of the dust plume with a dust transport model. The model results and the experimental data show similar times regarding the appearance of the dust plume over each EARLINET site. Dust optical depth from the model agrees in most cases to particle optical depth measured with the Sun photometers. The vertical distribution of the mineral dust could be satisfactorily reproduced, if we use as benchmark the extinction profiles measured with lidar. In some cases we find differences. We assume that insufficient vertical resolution of the dust plume in the model calculations is one reason for these deviations.
Tellus B 01/2009; 61(1):325 - 339. · 4.38 Impact Factor
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A Papayannis,
V Amiridis,
L Mona,
G Tsaknakis,
D Balis,
J Bösenberg,
A Chaikovski,
F De Tomasi,
I Grigorov,
I Mattis, [......], G Pisani,
F Ravetta,
V Rizi,
M Sicard,
T Trickl,
M Wiegner,
M Gerding,
R E Mamouri,
G D 'amico,
G Pappalardo
[show abstract]
[hide abstract]
ABSTRACT: 1] More than 130 observation days of the horizontal and vertical extent of Saharan dust intrusions over Europe during the period May 2000 to December 2002 were studied by means of a coordinated lidar network in the frame of the European Aerosol Research Lidar Network (EARLINET). The number of dust events was greatest in late spring, summer, and early autumn periods, mainly in southern (S) and southeastern (SE) Europe. Multiple aerosol dust layers of variable thickness (300–7500 m) were observed. The center of mass of these layers was located in altitudes between 850 and 8000 m. However, the mean thickness of the dust layer typically stayed around 1500–3400 m and the corresponding mean center of mass ranged from 2500 to 6000 m. In exceptional cases, dust aerosols reached northwestern (NW), northern (N), or northeastern (NE) Europe, penetrating the geographical area located between 4°W–28°E (longitude) and 38°N– 58°N (latitude). Mean aerosol optical depths (AOD), extinction-to-backscatter ratios (lidar ratios, LR), and linear depolarization ratios of desert aerosols ranged from 0.1 to 0.25 at the wavelength of 355 or 351 nm, 30 to 80 sr at 355 or 351 nm, and 10 to 25% at 532 nm, respectively, within the lofted dust plumes. In these plumes typical Saharan dust backscatter coefficients ranged from 0.5 to 2 Mm À1 sr À1 . Southern European stations presented higher variability of the LR values and the backscatter-related Å ngström exponent values (BRAE) (LR: 20–100 sr; BRAE: À0.5 to 3) than northern ones (LR: 30– 80 sr; BRAE: À0.5 to 1).
Journal of Geophysical Research 05/2008; 113(D10204). · 3.02 Impact Factor
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J. P. Taylor,
W. L. Smith,
V. Cuomo,
A. M. Larar,
D. K. Zhou,
C. Serio,
T. Maestri,
R. Rizzi,
S. Newman,
P. Antonelli, [......],
G. Grieco,
D. Summa,
R. Restieri,
G. Masiello,
F. Romano,
G. Pappalardo,
G. Pavese,
L. Mona,
A. Amodeo, G. Pisani
[show abstract]
[hide abstract]
ABSTRACT: The validation of advanced infrared sounding satellites requires a diverse set of coordinated synergistic observations utilizing ground-based and airborne instrumentation. T he European Aqua Thermodynamic Experi-ment (EQUATE) was held in September 2004 in both Italy and the United Kingdom to vali-date data from the Atmospheric Infrared Sounder (AIRS) instrument on the Earth Observing System (EOS) Aqua satellite. It also aimed to demonstrate how combinations of ground-based and airborne systems are useful for validating hyperspectral sat-ellite sounding observations from satellites due for launch through this decade. The era of hyperspectral atmospheric sounding began with the launch of the AIRS experiment of the EOS Aqua satellite during May 2002. Following AIRS, the Infrared Atmospheric Sounding Interferometer (IASI) was launched aboard the Meteorological Operational (METOP) polar-orbiting satellite in October 2006, and the Cross-Track Infrared Sounder (CrIS) instrument is to be orbited aboard the National Polar-Orbiting Environmental Satellite System (NPOESS) Prepatory Project (NPP) operational series of polar orbiters in late 2009. Operational geostationary satellite imaging hyperspectral sounding instruments, modeled after the experimental Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS), are being planned for implementation during the next decade. The focus of this initial experiment was placed on the validation of the AIRS instrument on the EOS Aqua satellite. During EAQUATE, the Proteus aircraft, carrying five separate remote sensing instruments [the NPOESS Airborne Sounder Testbed-Interferometer (NAST-I), NAST-Microwave (NAST-M), Scanning High-Resolution Infrared Sounder (S-HIS), Far-Infrared Sensor for Cirrus (FIRSC), and Microscale Measurement of Atmospheric Pollution Sensor (micro-MAPS)], was stationed in Naples, Italy, from 4 to 11 September and in Cranfield United Kingdom, from 11 to 19 September 2004. During the Italian portion of the campaign, Proteus underflew Aqua in coordination with ground-based remote sensing measurements, including several Raman lidar water vapor and temperature profilers and radiosondes, provided by
Bulletin of the American Meteorological Society. 02/2008;
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A Ansmann,
M Tesche,
D Althausen,
D Müller,
P Seifert,
V Freudenthaler,
B Heese,
M Wiegner, G Pisani,
P Knippertz,
O Dubovik
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[hide abstract]
ABSTRACT: 1] Multiwavelength lidar, Sun photometer, and radiosonde observations were conducted at Ouarzazate (30.9°N, 6.9°W, 1133 m above sea level, asl), Morocco, in the framework of the Saharan Mineral Dust Experiment (SAMUM) in May–June 2006. The field site is close to the Saharan desert. Information on the depolarization ratio, backscatter and extinction coefficients, and lidar ratio of the dust particles, estimates of the available concentration of atmospheric ice nuclei at cloud level, profiles of temperature, humidity, and the horizontal wind vector as well as backward trajectory analysis are used to study cases of cloud formation in the dust with focus on heterogeneous ice formation. Surprisingly, most of the altocumulus clouds that form at the top of the Saharan dust layer, which reaches into heights of 4–7 km asl and has layer top temperatures of À8°C to À18°C, do not show any ice formation. According to the lidar observations the presence of a high number of ice nuclei (1–20 cm À3) does not automatically result in the obvious generation of ice particles, but the observations indicate that cloud top temperatures must typically reach values as low as À20°C before significant ice production starts. Another main finding is that liquid clouds are obviously required before ice crystals form via heterogeneous freezing mechanisms, and, as a consequence, that deposition freezing is not an important ice nucleation process. An interesting case with cloud seeding in the free troposphere above the dust layer is presented in addition. Small water clouds formed at about À30°C and produced ice virga. These virga reached water cloud layers several kilometers below the initiating cloud cells and caused strong ice production in these clouds at temperatures as high as À12°C to À15°C.
J. Geophys. Res. 01/2008; 113.
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ABSTRACT: Three lidar stations located in Southern Italy were operational during the Italian phase of the EAQUATE campaign in September 2004. With this cluster of instruments, the characterization of water vapour and clouds distribution and evolution with high temporal and vertical resolution is possible. A cirrus cloud episode and the presence of an elevated humid layer in the free troposphere observed at all three stations are analysed in detail. Variability of both cirrus cloud and water vapour fields is studied on different spatial and temporal scales. Copyright © 2007 Royal Meteorological Society
Quarterly Journal of the Royal Meteorological Society 12/2007; 133(S3):257 - 271. · 2.91 Impact Factor
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[show abstract]
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ABSTRACT: 1] We summarize our Raman lidar observations which were carried out in Europe, Asia, and Africa during the past 10 years, with focus on particle extinction-to-backscatter ratios (lidar ratios) and Å ngström exponents. For the first time, we present statistics on lidar ratios for almost all climatically relevant aerosol types solely based on Raman lidar measurements. Sources of continental particles were in North America and Europe, the Sahara, and south and Southeast and east Asia. The North Atlantic Ocean, and the tropical and South Indian Ocean were the sources of marine particles. The statistics are complemented with lidar ratios describing aged forest fire smoke and pollution from polar regions (Arctic haze) after long-range transport. In addition, we present particle Å ngström exponents for the wavelength range from 355 to 532 nm and from 532 to 1064 nm. We compare our data set of lidar ratios to the recently published AERONET (Aerosol Robotic Network) lidar ratio climatology. That climatology is based on aerosol scattering modeling in which AERONET Sun photometer observations serve as input. Raman lidar measurements of extinction-to-backscatter ratios of Saharan dust and urban aerosols differ significantly from the numbers obtained with AERONET Sun photometers. There are also differences for some of the Å ngström exponents. Further comparison studies are needed to reveal the reason for the observed differences.
Journal of Geophysical Research 08/2007; 112. · 3.02 Impact Factor
