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Current Lidar Activities at ETL Mike Hardesty and Alan Brewer NOAA Environmental Technology Laboratory 24-May-17 Working Group on Spacebased Lidar Winds Overview of Topics • Fine structures of moisture transport measured during IHOP • Lidar upgrades and deployments for current field experiments • NOAA G-4 Doppler lidar 24-May-17 Working Group on Spacebased Lidar Winds IHOP Horizontal Winds: 9 June 270 km Forecast showed low level jet 24-May-17 Flight track to measure jet Working Group on Spacebased Lidar Winds Northern leg wind and water vapor 24-May-17 Working Group on Spacebased Lidar Winds Lidar and dropsonde flux comparison DIAL/Doppler lidar Dropsonde (~50 km spacing) 24-May-17 Working Group on Spacebased Lidar Winds Fine Scale Transport 1809 m ASL 24-May-17 Working Group on Spacebased Lidar Winds Fine Scale Transport 2309 m ASL 24-May-17 Working Group on Spacebased Lidar Winds Fine Scale Transport 2589 m ASL 24-May-17 Working Group on Spacebased Lidar Winds Average Moisture flux versus height 24-May-17 Working Group on Spacebased Lidar Winds Northern Leg vq Cospectrum 150 km 24-May-17 15 km Working Group on Spacebased Lidar Winds Current Lidar Activities • New England Air Quality (ship) – Wind profiler and Doppler lidar to characterize winds down to the surface – Cloud radar/radiometer to measure cloud properties – Aerosol/ozone lidar to detect layering – Air/sea flux measurements • New England Air Quality (plane) – Airborne ozone/aerosol lidar – Dropsondes • Key West Air Sea Interaction study – MOPA CO2 Doppler lidar on Navy ship 24-May-17 Working Group on Spacebased Lidar Winds High Resolution lidar 2003/2004 Upgrades • • • • • • • Reconfigured optical system to incorporate a fiber coupled receiver detector. Implemented a PZT controlled variable coupler to regulate amount of LO power mixing with return signal. Simplified transmit/receive paths. Completely re-designed receiver detector circuitry to be compatible with fiber receiver. Frequency monitor information now extracted from receiver detector signal. Implemented an improved PoundDrever/Hall circuit board (for locking cavity to seed light). Developed &implemented new motioncompensation control algorithms. – Correction to 0.3 degree rms – Fully removes linear velocities 24-May-17 Working Group on Spacebased Lidar Winds MOPA CO2 Doppler Upgrades • Implemented C12O18 isotope – Resonances in backscatter for some sulfates – Eliminates CO2 absorption – Reduced H2O continuum absorption • Two identical master oscillator paths for DIAL measurements • Range has doubled, often to 15 km with 1.3 mJ 24-May-17 ½ wave Shutters 12 Pass AOM1 AOM2 Pol BS CW Lasers Local Oscillator RF Discharge Optical Amplifiers Cooled Detector 1/4 wave 6 Pass Pol BS Working Group on Spacebased Lidar Winds 8 “ Off Axis Parabolic Telescope NOAA G-IV Instrumentation Upgrades Contact Point: Alan S. Goldstein – NOAA/Aircraft Operations Center 24-May-17 Working Group on Spacebased Lidar Winds Mission Needs • The next generation of NWS numerical prediction models is the Weather Research and Forecasting (WRF) system. The WRF for hurricanes (HWRF) will be an advanced modeling system to forecast track, intensity and rainfall. • NWS held a workshop in May 2002 to identify data required by HWRF. The results of this workshop were used to generate a preliminary instrumentation and modification plan. • Discussions with NCEP/Environmental Modeling Center, NCEP/National Hurricane Center and OS/Operations and Requirements Division have refined the measurement requirements and corresponding instrumentation proposal. 24-May-17 Working Group on Spacebased Lidar Winds 1 HWRF Workshop List • • • • • • • • 3D Winds – Critical for Model Initialization _ Ocean Temperature and Heat Content * | For Model Vertical Temperature Profiles | Verification Vertical Moisture Profiles | (May be needed Ocean Waves * _| for initialization) Microphysics/Rain | Ocean Currents | For Model Radiation | Verification * Supports current NHC forecasting 24-May-17 | _| Working Group on Spacebased Lidar Winds 1 Look angles and wind products 24-May-17 Working Group on Spacebased Lidar Winds 2-d Winds in each plane Mean Wind 24-May-17 Working Group on Spacebased Lidar Winds Components Spec • Value Notes Measurement rate: 2 seconds per look angle Includes integration time and articulation Measurement spatial resolution: 1 km LOS Look directions: 4 or 6 points / 2 or 3 planes 0, +/-5 deg (elevation). Fore and aft (45 deg) Laser wavelength: 355 nm Laser power: 12 watts Laser rep rate: Laser Eye safety – Diode pumpedMeasurement tripled Nd:YAG accuracy: Telescope type: • • • Telescope aperture: Receiver Telescope field of view: – Direct detection < 1 m/s from 0 – 15 km HOE Telescope/Scanner 18 cm (30 cm) .2 mrad 1.6 cm Number of orders: 5 Heat Rejection Free spectral range: Dynamic range: – Cooling Loop to external radiator .3125 cm-1 1644 m/s/order Etalon plate diameter: 6 cm Etalon clear aperture: 4.2 cm Telescope/ScannerEtalon reflectivity: – HOE scanner (Schwemmer) Etalon flatness: Number of CCD channels: Integration/Products Transmission to interferometer input: – NOAA/ETL Overall transmission: 24-May-17 Eye safe Etalon gap: Etalon absorpotion: • 50 Hz diode pumped 70% Lambda / 150 @ 633 nm <1% 283 41% 17% Recycling configuration 3 Operation: Autonomous with scripting Working Group on Spacebased Lidar Winds Interior view 24-May-17 Working Group on Spacebased Lidar Winds Expected Performance 24-May-17 Time resolution 2 secs Along beam spatial resolution 1 km 4 point scan 6 point scan 8 secs 12 secs Wind profile flight path spatial scale 2 km to 3 km Working Group on Spacebased Lidar Winds Timeline • April 04 – Paperwork into purchasing – NASA MOU paperwork into system • • • • • • • Sep 04 – Orders placed July – Sept 05 Delivery of major components Sept – Nov 05 Assemble Lidar system Nov 05 - Lab testing entire system Dec 05 - Initial upload of Lidar into G4 Winter Storm Season 06 - testing Lidar systems Hurricane Season 06 – Initial deployment G4 Doppler Lidar 24-May-17 Working Group on Spacebased Lidar Winds What’s next • IHOP – Compare observed transport with model estimates – Complete investigation of vertical velocity fluctuations • Solid state Doppler lidar – Tropical cumulus experiment (NOAA ship) 2005 – Fly on NOAA Twin Otter (2005) – Co-deploy with airborne ozone lidar in Texas (2006) • Dual wavelength CO2 MOPA lidar – DIAL experiments to measure hydrocarbons 24-May-17 Working Group on Spacebased Lidar Winds