Developments with DORIS

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Developments with DORIS

• Laurent Soudarin CLS
• Jean-François Crétaux CNES

Workshop on new technical developments in sea and
land level observing system Paris, Unesco 2003
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(No Transcript)
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Doris network
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Satellites

90 91 92 93 94 95 96 97 98 99
2000 01 02 03 04 05 06 07
SPOT2
SPOT4
TOPEX-POSEIDON
JASON1
SPOT3
ENVISAT1
SPOT5
CRYOSAT
JASON2
PLEIADES
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Main Doris Applications

• Orbit determination
• Cm accuracy with JASON
• Real-time onboard orbit 15 cm
• Positioning of the beacons
• Reference frame to IERS (since 1994)
• Geocenter and polar motion
• Horizontal/vertical crustal deformations

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Performances

• Satellites in orbits
• 1990, 1 satellite 4 cm
• 1993, 2 satellites 2.5 cm
• 1994, 3 satellites 1.5 cm
• 2002, 6 satellites lt 1cm
• Gravitational models
• 1994, JGM2 1.5 cm
• 1998, EGM96 1.2 cm
• 2000, Grim5 1cm
• 2005, GOCE ?????

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Collocations

• Orbital
• DORIS-SLR Topex / Poseidon Envisat
• DORIS-SLR-GPS JASON-1
• Network
• DORIS-SLR 7 sites
• DORIS-GPS 28 sites
• DORIS-VLBI 9 sites
• DORIS-Tide gauges 14 sites

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Sea level Change Monitoring

• Tide Gauge
• Historical data, non uniform coverage,
• relative sea level (crustal deformation)
• Satellite altimetry
• Absolute sea level, global coverage,
• instrumental drifts

gtCalibration of satellite altimetry using tide
gauge sea Level, estimation of vertical crustal
motion DORIS-GPS-SLR
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Thule
St John
Punta Delgada
Socorro
Manille
Palmeira
Clipperton
Mahe
Fernando
Santa Cruz
Ascension
Rikitea
St Helene
Papetee
Noumea
Easter Island
Chatham
Crozet
Kerguelen
Terre Adélie
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What should we expect from an international Doris
Service?

• Enhanced international coordination
• More analysis centers
• Stronger participation in IERS
• gt better Doris products

http//ids.cls.fr
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Conclusion

• New era for Doris system development
• 3 new satellites
• Extension of network
• New generations of geopotential models
• IDS elected as fundamental services of IAG
• Perenity of the system
• Accuracy improved
• Support for other disciplin like oceanography
• as orbital tracking system of altimetry missions
• as geodetic tool for monitoring vertical
  displacement of tide gauges