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POLIS – Portable Lidar System
High Resolution Cloud Top Height Measurements using an Airborne
Lidar System during BBC 2 Campaign May 2003 Birgit Heese
Meteorological Institute University of Munich (MIM)
Airborne campaign BBC 2 onbord the Do 228 (NERC) in collaboration with FU Berlin
May 5 – 10, 2003
POLIS – Portable Lidar System
High resolution cloud top height measurements
Single pulse measurements were performed at a repetition frequency of the laser of 5 Hz
• horizontal resolution is about 16 m (plane velocity ~ 80 m/s)
• vertical resolution of 7.5 m
POLIS – Portable Lidar System
Single pulse lidar profile
POLIS – Portable Lidar System
0
500
1000
1500
2000
0 200 400 600 800 1000 1200
Intensity of Backscatter Signal
Cloud signature in the Lidar signal
Dis
tanc
e fr
om p
lane
/ m
Cloud top height at a distance of 1227 m from the plane
flight level
The lidar signal is
not range corrected!
Single pulse lidar profile
POLIS – Portable Lidar System
Ground return of the lidar signal at a distance of 3646 m from the plane
Cloud top height from former picture is at 2369 m
flight level0
500
1000
1500
2000
2500
3000
3500
4000
0 200 400 600 800 1000 1200
Ground return signature in the Lidar signal
Intensity of backscatter signal
Dis
tanc
e fr
om p
lane
/ m
The lidar signal is
not range corrected!
Available Datasets
Flights took place on May 6, 7, and 10, 2003
May 6: 14:06:37:36 – 14:31:04:77 (1 pulse)May 7: 11:40:48 – 11:47:40 (200 pulses) Aerosol measurements
12:34:32 – 13:18:56 (200 pulses) 13:23:58:16 – 14:34:33:56 (1 pulse)
May 10: 12:22:26:10 – 12:22:35:32 (1 pulse) 12:35:32:25 – 14:48:34:09 (1 pulse)
2nd flight: 16:22:27:47 – 17:05:08:41 (1 pulse)
POLIS – Portable Lidar System
Some views out of the plane Cabauw site
Clouds on May 10, 2003
POLIS – Portable Lidar System
Lidar Backscatter Signal on May 10, 2003
POLIS – Portable Lidar System
1000 profiles:
Not all details
are resolved
These lidar signals
are range-corrected!
flight level !
Lidar Backscatter Signal – Cloud Top Height
POLIS – Portable Lidar System
200 profiles
Flying into a cloud
POLIS – Portable Lidar System
0 500 1000 1500 2000 2500 3000 3500
time12:36:08:12B
12:36:08:36C12:36:08:54D
12:36:08:71E12:36:08:92F
12:36:09:12G12:36:09:35H
12:36:09:54I12:36:09:74J
12:36:09:92
Time series of lidar backscatter signal from a cloud
Distance from plane / m
flight level !
Data Type
• Calculation of the cloud top height from Lidar profiles and navigation data (flight altitude, coordinates) will be stored in the database
• Quicklook plots in the form as shown in this presenstation can also be provided.
• Lidar profiles themselves are not of much use for the BBC community
• If there are any other requirements, please write to:
POLIS – Portable Lidar System
Acknowledgements
MIM: Volker Freudenthaler, Miriam Kosmale, Anton Lex, Meinhard Seefeldner, Matthias Wiegner
FU Berlin: Thomas Ruhtz
Marc Schröder
NERC: Carl Joseph Adam Edgar
POLIS – Portable Lidar System
