A Permanent GPS Array in Crete & the Cal/Val facility for satellite radar altimeters in Gavdos

Transcription

1 A Permanent GPS Array in Crete & the Cal/Val facility for satellite radar altimeters in Gavdos S. P. Mertikas Technical University f Crete EUREF 2007 Symposium, June 2007, London, England Laboratory of Geodesy and Geomatics Engineering

2 Ground tracks of Jason-1

3 Principle of operation

4 Regional Bathymetry

5 Equipment locations

6 Harbor site in August 2002

7 Harbour site in April 2005 Ashtech GPS receiver operates EUMETSAT antenna. Site sends data to Central Facility, Pressure tide gauge transmits every 20 minutes, Acoustic tide gauge transmits every 6 minutes.

8 New tide gauge with GPS ready

9 Central permanent site Normal operation, DORIS beacon as IDS station GPS Leica RS500 Weather Station transmits every 20 min

10 Transponder cross-over over

11 Communication links UHF line is operational. Omalos 10 Watts TUC 10 Watts GPRS link through Vodafone mobile network and with static IPs ready. An ISDN line at Central permanent facility. Sougia 10 Watt s 10 Watts Gavdos

12 EUREF sites

13 Operations Control Center GPS receiver CD archive Main server: data collection, storage, and processing Meteo station Communication facilities Tape drive LAN Firewall GPS controller Data analysis cosmos: http and misc server Internet

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15 Leveling at Gavdos Karaves Theophilos

16 FTLRS Satellite Laser Ranging

17 SLR measurements

18 SLR observations (2003.0)

19 Geoid map

20 1 X1 Geoid model

21 Jan 2003 Airborne Campaign

22 Airborne campaign

23 Airborne gravity campaigns

24 Airborne laser altimetry

25 GPS buoys experiment

26 Sea level -Hydrodynamic modeling

27 Sea Surface Topography

28 Absolute bias for Jason-1 Pass 18 Pass 109 Combined to mm to mm to mm

29 Bias comparisons Facility Orbit Events Mean ± std. error (mm) σ (mm) Harvest CNES POE ±7 41 Harvest JPL GPS ±6 34 Corsica CNES POE ±7 35 Corsica JPL GPS ±7 36 Bass strait CNES POE ±6 42 Bass strait JPL GPS ±6 40 UK group CNES POE 387 * +137±30 80 UK group CNES POE ±30 71 GAVDOS 1 CNES POE ±20 80 GAVDOS 2 CNES POE ±15 47

30 Jason microwave radiometer calibration Comparisons of JMR, GEMOSS (ETHZ, Swiss) and WVR. (132.4 ±7.4 mm, ±2.0 mm and ±5.0 mm). Results agree at the level of millimeters. Fiskardo Gerogombos Jason encounter: Sept. 20th, 2003

31 The new jetty construction

32 Future west Crete GPS array KSL1 for Cal/Val CHR1 for geodynamics SFK1 for geodynamics and silent earthquakes RTM1 in the Institute of Mediterranean Studies Real-time & post-processed processed services.

33 Tectonics & deformation

34 Hellenic Positioning Service 95 permanent GPS stations Will provide real-time and post-processed processed services Nationwide & ITRF based ADSL connections Trimble sets it up in 2007 Trimble will operate it till 2008 Hellenic Mapping & Cadastral Organization.

35 Future plans Continue monitoring satellite altimetry for calibration/validation. on. Transmit reliably, securely and immediately Cal/Val data. Transmit GPS data to ASI (Italy) & BKGE (Germany), OLG (Austria). Develop procedures for automatic analysis and archiving of data. Extent capabilities to Geosat-Follow Follow-On, Cryosat-2, Jason-2: Ocean Surface Topography Mission, etc. Officially engage Gavdos to IGS, Med-GLOSS, ESEAS, Poseidon, etc.