G O D D A R D S P A C E F L I G H T C E N T E R Goddard Lidar Observatory for Winds (GLOW) Wind Profiling from the Howard University Beltsville Research Facility Huailin Chen, Bruce Gentry, Tulu Bacha, Belay Demoz, Demetrius Venable Destin, FL February , 2010
Goddard Lidar Observatory for Winds (GLOW) Wind Profiling from the Howard University Beltsville Research Facility. Huailin Chen, Bruce Gentry, Tulu Bacha, Belay Demoz, Demetrius Venable Destin, FL February , 2010. - PowerPoint PPT Presentation
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G O D D A R D S P A C E F L I G H T C E N T E R
Goddard Lidar Observatory for Winds (GLOW) Wind Profiling
from the Howard University Beltsville
Research Facility Huailin Chen, Bruce Gentry, Tulu Bacha, Belay Demoz, Demetrius
Venable
Destin, FLFebruary , 2010
G O D D A R D S P A C E F L I G H T C E N T E R
NASA Wind Lidar Science (WLS) Experiment at Howard Beltsville
Research FacilityGOALS
• Develop understanding of direct detection (GLOW) wind speed and direction performance for various cloud and aerosol loading conditions (pollution, cirrus), using the 355nm backscatter ratios and water vapor data independently measured by the Raman lidar as well as synergistic measurements from the Beltsville instrument suite.
• Develop a seasonal data base archive for wind measurements.
• Intercomparison of coherent and direct detection Doppler lidars
• Compare Doppler lidar wind data to other sensors (Profiler, Radiosonde, ACARS).
Funded by NASA SED, ROSES07-WLS (Dr. Ramesh Kakar)
G O D D A R D S P A C E F L I G H T C E N T E R
Overview for GLOW
Measurement summary •Vertical resolution=250 m t=3 min •Altitude range= 2 to 15 km•Elevation angle= 45 deg•Scan pattern = 4 directions: (N,S,E,W)+vertical•Dwell per LOS = 30 sec
Goddard Lidar Observatory for Winds (GLOW) mobile Doppler lidar
• Direct detection Doppler Lidar system• Measures clear air wind profiles using molecular backscatter• Serves as testbed for air and space based lidar technologies• Multiple field campaigns since 2000
Line of sight wind profiles are sequentially measured at 4 azimuth angles (N,S,E,W)+vertical. The multiple direction LOS profiles are combined to produce vertical profiles of horizontal wind speed and direction (right)
Sampling strategy:• LOS scans at multiple azimuths in repeating cycle (5-10 LOS /cycle)
• Step stare scan pattern at fixed elevation angle (Typ. 45 deg) : 4 cardinal directions (N,S,E,W) + vertical
• Signals are range gated in 30 m bins, integrated and stored every 10 s. Three dwells (30s total) per LOS. Total time to complete scan: ~3 min
Post processing: • data averaged in range (default 250 m)• data can be accumulated in time by LOS (multiples of base 3 min)• corrections for atmos. T and P (RBS)
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