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| Titel |
Scanning Mobile Lidar for Aerosol Tracking and Biological Aerosol Identification |
| VerfasserIn |
Tingyao He, Klemen Bergant, Andrej Filipčič, Biagio Forte, Fei Gao, Samo Stanič, Darko Veberič, Marko Zavrtanik |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250033839
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| Zusammenfassung |
| Optical properties of non-biological aerosols containing aromatic hydrocarbons, such as
industrial chemicals and engine exhausts, have already been thoroughly studied using remote
sensing techniques. However, because of their complex composition and characteristics, the
identification of biological aerosols, such as fungi, pollen and bacteria that are present in the
environment remains a rather difficult task. The collection of information on both
non-biological and biological aerosols is of great importance for understanding their
interrelation, physical and chemical properties and their influence on human health and the
environment.
Biological and non-biological aerosols can be simultaneously detected, tracked and
identified by a scanning mobile Mie-fluorescence lidar. The device developed at the
University of Nova Gorica can perform azimuth and zenith angle scans with an
angular resolution of 0.1-, as well as operate in both day and night-time conditions.
Aerosols of biological origin are identified through the detection of the fluorescence of
the amino acid tryptophan which is present in almost all substances of biological
origin.
In our system, the transmitter is a solid state Nd:YAG laser which is capable of
simultaneous emission of light at a base wavelength of 1064 nm (IR) and its quadrupled
wavelength of 266 nm (UV) at a maximum repetition rate of 10 Hz. Tryptophan contained in
biological aerosols is excited by the 266 nm laser pulses and the returning fluorescence
signals are detected in the spectral band centered at 295 nm. The receiver is a Newtonian
telescope which uses a 300 mm parabolic mirror to direct received light into three
detection channels – two elastic backscatter channels (IR and UV) and a fluorescence
channel.
First experiments show that the detection range of the lidar reaches 10 km in the IR
channel and 3 km in the UV channel. Based on the preliminary simulations of the
signal-to-noise ratio, the detection range for biological fluorescence signals at 295 nm is
estimated to be 2 km. The measurements of the time-series indicate that the mobile lidar is
capable of detecting and profiling clouds and aerosols in its detection range. Our future plans
include establishing an automated, unattended environmental monitoring system that will
allow full time continuous measurements in the desired solid angle around the lidar station. |
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