daniel roman, marc véronneau , david avalos, xiaopeng li, simon holmes, and jianliang huang
DESCRIPTION
Integration of Gravity D ata I nto a Seamless T ransnational H eight M odel for North America. Daniel Roman, Marc Véronneau , David Avalos, Xiaopeng Li, Simon Holmes, and Jianliang Huang Session 5: Paper S5-075. Gravity for the Redefinition of the American Vertical Datum (GRAV-D). - PowerPoint PPT PresentationTRANSCRIPT
Integration of Gravity Data Into a Seamless Transnational Height
Model for North AmericaDaniel Roman, Marc Véronneau, David Avalos, Xiaopeng Li, Simon
Holmes, and Jianliang Huang
Session 5: Paper S5-075
Gravity for the Redefinition of the American Vertical Datum (GRAV-D)• Overview• Not just aerogravity – Use to clean/salvage two
million terrestrial data– Makes improved geoid– Must use satellite data– Yields a vertical datum
• Neighboring countries– Must develop a North
America Model
Session 5 Paper S5-075 1730 10 OCT 2012
Gravity Geoid and Height Systems Venice, Italy 09-12 OCT 2012 2
GRAV-D Status
Session 5 Paper S5-075 1730 10 OCT 2012
Gravity Geoid and Height Systems Venice, Italy 09-12 OCT 2012 3
TX09
Discussion of GRAV-D intent
• Goal of a cm-level accurate geoid• Must meld different gravity sources• To do this: must resolve systematic
errors in gravity observations– Compare aerogravity to satellite data – Constrain aerogravity to GRACE/GOCE– Combined satellite & airborne gravity field
model- somewhere between deg 100-250– Use aerogravity to fix errors and bridge
spectral gap with terrestrial surveys– Derive shortest wavelengths from high
resolution terrain and density models– Develop a seamless gravity field to 10,800
• Rigorously transform to generate geoid heights and DoV’s
4
1.E-08
1.E-06
1.E-04
1.E-02
1.E+00
1.E+02
1.E+04
satellite models (GRACE/GOCE)
terrestrial gravity
airborne gravity
Var
ian
ce (
m2)
Satellite-AirborneTransition Band
Airborne-Terrestrial Transition Band
Session 5 Paper S5-075 1730 10 OCT 2012
Gravity Geoid and Height Systems Venice, Italy 09-12 OCT 2012
ATTB: 150-450 (100-540 with tapers)
More clear short wavelength Systematic features in Historical surface data are detected after adding airborne information
Summary
• GOCO03S benefits EGM2008• Systematic errors in terrestrial data still exist• Such errors lead to systematic geoid errors• Must resolve these for cm-level accuracy• Aerogravity in Texas differs from terrestrial at
the 3-5 mGal range• Can be discerned in some terrestrial profiles• Data cleaning will be required to resolve theseSession 5 Paper S5-075 1730 10 OCT 2012
Gravity Geoid and Height Systems Venice, Italy 09-12 OCT 2012 13