WEGENER Nice 2006 OLG Monitoring of the Eastern Mediterranean and Arabia Velocitiy Estimations of Permanent GPS Stations 1Space Research Institute, Austrian Academy of Sciences 2Federal Office of Metrology and Surveying (BEV) Cornelia Haslinger 1, Günter Stangl 2

WEGENER Nice 2006 MON Mediterranean Oriental Network 50 Stations

WEGENER Nice 2006 Processing Weekly results (EPN standards, Bernese Software ) since 2000, extended to Indian Ocean 2000/1 and 2006 Reference Minimum constraint solution on BUCU, GRAZ, SOFI with IGS/EPN ITRF2000 coordinates and velocities EPN offsets for IGS/EPN stations applied Raw time series checked for outliers (isolated values lateral >10 mm, vertical >20 mm) Outliers removed  cleaned time series 50 Station velocities estimated (9 too short), BSW formal sigmas 0.1 mm/year ITRF2000 rotation of Eurasia (Altamimi, Boucher 2002) removed -> velocities relative to Eurasia Comparison to values of EPN, MIT (Reilinger et al. 2006), SOPAC

WEGENER Nice 2006 MON Station Lateral Velocities

WEGENER Nice 2006 MON Station Vertical Velocities AMMN, NAMA, SOLA Probably computational artefacts or local effects

WEGENER Nice 2006 Time Series New IGD1/NOA1 IGD1 (Athens) velocities similar to DION (Dionysos) NOA1 (Athens) still too young

WEGENER Nice 2006 Time Series New AUT1

WEGENER Nice 2006 Changing Velocity MIT pre-earthquake velocity (1998/9) OLG velocity after – difference 5 mm/year

WEGENER Nice 2006 Time Series Problems (1) Gap by missing data - jump at restart ?

WEGENER Nice 2006 Time Series Problems (2) Large up velocity, but time series ok

WEGENER Nice 2006 Time Series Seasonal Effects (1)

WEGENER Nice 2006 Time Series Seasonal Effects (2)

WEGENER Nice 2006 Time Series Seasonal Effects (3)

WEGENER Nice 2006 Time Series Seasonal Effects – Model Effect? BSW 5.0 Niell Dry+Wet Tropospheric gradients BSW 4.2 Dry Niell

WEGENER Nice 2006 Comparison of Velocities OLG time series <26 weeks excluded OLG-EPN 14 stations <5 mm/year 5 stations 5-10 mm/year (ANKR, DRAG, RAMO, TRAB, all Up bias 7 mm/year, EPN problem) OLG-MIT 24 stations <5 mm/year 4 stations 5-10 mm/year (MALI, POL2, SEY1, OLG problem, TUBI MIT problem) OLG-SOPAC 17 stations 10 mm/year (AMMN, DGAR, MALD, POL2, SEY1, OLG problem, HALY, TEHN SIO problem) New stations (no comparison possible) AUT1, IGD1

WEGENER Nice 2006 Conclusions Time series and 3D-velocity estimations of OLG cover a time span Permanent GPS stations in the Eastern Mediterranean monitored, most EPN corrections applied IGS reference sites outside Europe included, but too short for reference->EPN referenced Annual term in BSW 4.2 time series can be reduced by introducing a more refined model of the troposphere Very good fit to GPS velocities of (Reilinger et al. 2006) Reprocessing planned with ITRF2005 and absolute phase calibrations + improved model of the troposphere

WEGENER Nice 2006 Thank You !