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ADM A tmospheric D ynamics M ission Second ESA Earth Explorer Core Mission. Mission goal To determine profiles of one component of wind speed from ground up to 20 km with accuracy better than 2 m/s in troposphere with global coverage Core Instrument
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ADMAtmospheric Dynamics Mission Second ESA Earth Explorer Core Mission Mission goal To determine profiles of one component of wind speed from ground up to 20 km with accuracy better than 2 m/s in troposphere with global coverage Core Instrument Incoherent Doppler Lidar @ 355 nm pointing 35 ° off Nadir Benefit NWP and Climate Studies Single Payload Mission Launch: fall 2007
U-Wind Accuracy 250 hPa, 12 h Forecast 31 days October 2000, mean of 10 assimilation ensembles from: Erik Andersson, David Tan (ECMWF)
WMO Expert Team ON OBSERVATIONAL DATA REQUIREMENTS AND REDESIGN OF THE GLOBAL OBSERVING SYSTEM Summary of Statement of Guidance for Global NWP (July 2002) The critical atmospheric and surface parameters (in order of priority) that are not adequately measured by the current or planned observing systems are: • wind profiles at all levels; • temperature profiles of adequate vertical resolution in cloudy areas; • precipitation; • soil moisture; • surface pressure; • snow equivalent water content; High Priority System Specific Recommendations for Additional Capabilities in the Space Based Component of GOS (in order of priority for each category) • R&D satellites • LEO Doppler Winds - Wind profiles from Doppler lidar technology demonstration programme (such as Aeolus) should be made available for initial operational testing; a follow-on long-standing technological programme is solicited to achieve improved coverage characteristics and reduced instrument size necessary for operational implementation.
Ground Track over Germany Mission Requirements • Mission Requirements • • Height vert. res. HLOS / LOS accuracy • 0 - 2 km 0.5 km 1 m/s 0.6 m/s • 2 - 16 km 1.0 km 2 m/s 1.2 m/s • 16 - 27 km 2.0 km 3 m/s 1.7 m/s • unknown bias 0.4 m/s • slope error 0.7 % (wind speed dependent error) • • 3000 profiles per day • data availability 3 hours • mission lifetime 3 years • October 2003 start phase C • launch 2007 - only 2.5 years !!!
AEOLUS Satellite and Instrument ALADINAtmospheric Laser Doppler Instrument Budgetsmass: 1242 Kg (instrument 446 kg)power: 1344 W (instrument 866 W) Doppler Lidar Instrument ALADIN Nd:YAG laser-transmitter in burst mode (150 mJ @ 355 nm, 100 Hz)1.5 m Cassegrain telescopeDual-Channel-Receiver with ACCD (Accumulating CCD Detector) Pointing and Orbit ControlGPS, Star-Tracker, Inertial Measurement Unit, Yaw steering to compensate for earth rotation LauncherRockot (SS-19 ICBM), Dnepr (SS-18 ICBM) or Vega (ESA development) from EADS- ASTRIUM
Telescope Background Interference-Filter Beam Splitter Double Edge Fabry-Perot Fizeau Interferometer Mie Receiver Rayleigh Receiver from EADS-ASTRIUM, Toulouse ALADIN Receiver Design
Do we need pre-launch campaigns? • New technology used including ACCD, novel dual spectrometer combination with Mie and Rayleigh receiver, Fizeau for Mie-Receiver, sequential Fabry-Perot • Extensive laboratory characterisation of system by industry, but only fewatmospheric measurements => it is a LIDAR: complexity of instrument + atmosphere • Error assessment with simulations including standard atmosphere are only partly valuable • No airborne demonstration of wind measurements with direct-detection system => majordifferences between ground based systems and airborne/satellite systems • Extensive data set for testing and validating of Level1b-Processor and End-to-End Simulator 2006 2006 Sept 2005
ALADIN Airborne Demonstrator A2D (1/3) Figure EADS-Astrium, Sept. 2004
ALADIN Airborne Demonstrator A2D (2/2) Fig. by EADS-Astrium, Sept. 2004
Meteorological Observatory Lindenberg MOL • Windprofiler site: • 482 MHz windprofiler with RASS (wind up to 16 km, temp. up to 3 km) • 1290 MHz windprofiler (wind up to 1.5 km) • 35.5 GHz cloud radar (relecivy, vertical velocity) • Main building (distance1 km): • Laser Ceilometer (clouds 12 km, aerosol backscatter in boundary layer) • microwave radiometer (profiles of water vapor and temperature up to 10 km) • Optic laboratory (distance 500 m): • 355 nm Raman-lidar (profiles of water vapor during night) • Sun and star photometer (Optical depth day and night) • Additional: • 4 routine radiosondes per day • tethered balloon system • Falkenberg site (distance 5 km): • SODAR/RASS (wind, temp. up to 500 m) • 100 m Turm (wind, temp, humidity, turbulence) • 1 long-range, 1 short-range scintillometer (turbulence)
Status and Outlook • Receiver breadboard of A2D manufactured and extinsively tested in laboratory by EADS-Astrium, France • A2D laser transmitter setup by EADS-Astrium, Germany (70 mJ@355 nm achieved;frequency stability shot-to-shot of 1.4 MHz@1064 nm rms) • Manufacturing of thermal hood and regulation, airborne front optics, telescope tube ongoing • Performance test at EADS-Astrium, France in May-June 2005 • Functional tests at DLR in June-August 2005 with first atmopheric measurements • Ground campaign in Lindenberg in September 2005 • First functional test flights in early 2006 • First airborne campaign in April 2006