1 / 19

Towards the Next Earth Gravitational Model to Degree 2160: Status and Progress

Towards the Next Earth Gravitational Model to Degree 2160: Status and Progress. Dynamic Planet 2005 Cairns, Australia 22-26 August 2005. Steve Kenyon , John Factor, NGA Nikolaos Pavlis, Jarir Saleh, Simon Holmes, Raytheon IS. Earth Gravitational Model 2006.

donagh
Download Presentation

Towards the Next Earth Gravitational Model to Degree 2160: Status and Progress

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Towards the Next Earth Gravitational Model to Degree 2160: Status and Progress Dynamic Planet 2005 Cairns, Australia 22-26 August 2005 Steve Kenyon, John Factor, NGA Nikolaos Pavlis, Jarir Saleh, Simon Holmes, Raytheon IS

  2. Earth Gravitational Model 2006 • CHAMP and GRACE satellite gravity missions • 100x improvement in the accuracy with which large regional features of the gravitational field can be modeled • Need for higher-resolution model of the gravitational field and geoid • 5’ x 5’ resolution • n=m=2160 • 15 cm global RMS accuracy goal for geoid

  3. EGM96 30’x30’ resolution 50 cm RMS accuracy 70 x 70 error propagation 40 satellites used for long ’s 30 M surface gravity values 29 elevation codes 130 K coefficients EGM06 5’x5’ resolution 15 cm RMS accuracy 2160 x 2160 error propagation CHAMP and GRACE used for long ’s 52 M surface gravity values SRTM, ICESAT 4.7 M coefficients Progression of EGMs

  4. EGM06 Geoid Goals • EGM06 Geoid Error Goal - 15 cm Global RMS • 5 cm commission error from GRACE out to n=m=100 • 3 cm omission error beyond 2160 following Kaula's Rule • NGA’s detailed gravity data are expected to meet an ~14 cm geoid commission error requirement for degrees 101-2160

  5. EGM06 Geographic Accuracy Breakdown • Ocean areas with good altimetric data: from +/- 5 cm to +/- 10 cm • Land areas with good surface gravity data: from +/- 10 cm to +/- 15 cm • Land areas with poor surface gravity data: from +/- 15 cm to +/- 50 cm • Land areas with no surface gravity data: from +/- 50 cm to +/- 120 cm

  6. UNCLASSIFIED Data Collection Methods

  7. Statistics of 5’x5’ g (v081005) Source  Area Min. Max. RMS  ArcGP 4.0 186.0 235.6 31.3 8.1 Altimetry 67.0 -360.4 377.9 29.2 3.1 Terr. 15’ 18.0 -284.5 443.8 42.3 6.1 Fill-in 3.2 -196.9 256.4 32.3 24.6 Actual 5’ 78.8 -360.4 669.8 29.6 3.6 All 100.0 -360.4 669.8 32.3 6.0 (, ) 19.5, 293.5 19.5, 204.5 The Fill-in anomalies for v081005 have decreased from 16.7 to 3.2  of the world compared to PGM2004A

  8. Mongolian Aerogravity Project

  9. JGP95E 5’x 5’ Global Elevation Source Codes

  10. SRTM World Coverage Map Coverage between latitudes 60 N - 54 S 80% of the Earth’s landmass

  11. KINEMATIC GPS GROUND CONTROL POINT COMPARISON WITH SRTM

  12. KMS 2002 2’x2’g RMS = 2.9 mgal in comparison with NGA’s “Best” Marine 5’x5’ File

  13. GPS/Leveling Comparisons (±2 m edit threshold) Weighted Mean Std. Deviation (cm)

  14. GPS Leveling Comparisons over Some Areas with New g Statistics before bias removal. 2 m edit applied.

  15. Upcoming EGM06 Activities • Spherical harmonic synthesis software will be made available at end of 2005 • Official EGM06 project software • Provides ability to efficiently compute geodetic quantities to n=m=2160 • Test sets to be provided • Available thruhttp://earth-info.nga.mil/GandG/ • Validation of new EGM06 • GPS/leveling, orbits, DOVs, etc. • International participation is welcome • Spring 2005 timeframe leading to final EGM06 selection

  16. Summary • EGM06 is planned for June 2006 • New surface and airborne gravity collected until Jan 06 • Goal of EGM06 is 15 cm • n=m=2160 • 5’x5’ resolution • Latest GRACE model, Surface Gravity, Satellite Altimetry, SRTM and ICESAT data will be utilized • Error Propagation to n=m=2160 • 5’x5’ gravity data from unsurveyed areas is welcome

More Related