USGG2012/GEOID12 Research & Development

Geoid TeamDan Roman, Yan Wang

Xiaopeng Li & Simon Holmes

Discussion Items

• W0 determination• Leveling Adjustments• NA2011• GPSBM2012 • OPUS-DB• Timeline & Coordination

W0 determination

• Canada to use geoid-based vertical datum 2013– Needs a decision on final W0 by 01 APR

• Analysis based on TBM’s & MSSH data using USGG2009 & CGG2010 and various MODT – Pacific analysis complete (NOV)– Atlantic in progress (JAN)– Gulf of Mexico and Arctic models still required (FEB)– Aim is to determine any offset from current W0

– Jointly decide on best W0 to use in USGG2012/CGG2013

Leveling Adjustments

• NA2011 PID’s sorted to find those on bench marks with leveled heights (forms GPSBM2012)

• Preliminary list (focusing on leveled heights only) provided to State Advisers Plus for analysis in NOV

• Updated list due out this month• Awaiting adjustments for WI, MS, LA, TN, & AL– WI likely finished by middle of MAR

• Final assessment of leveled heights in late MAR when final GPSBM2012 list goes out

NA2011

• Coordination is ongoing with NA2011 Team• Final NA2011 values likely delivered in FEB for

internal use of Geoid Team• The NA2011 values will be integrated with

leveling to form GPSBM2012 to make GEOID12• Release of GEOID12 will be coordinated with

NA2011 release in early April

GPSBM2012

• Composed of leveled heights & NA2011 ellipsoid coordinates

• NA2011 “final” coordinates delivered in FEB• Final leveling determined after WI adjustment• These will be used to make a final GEOID12• They will also be sent out in middle MAR to

State Advisers Plus for one last scrub

OPUS-DB

• NA2007 => NA2011 conversion in early FEB• Points will be checked to supplement NGSIDB

values given in GPSBM2012• Focus will be filling voids in western states• List will be sent out with GPSBM2012 updates• Final NA2007 => NA2011 conversion in late

APR

Timeline & Coordination• January– 2nd iteration of leveling out to State Advisers Plus

• February– W0 analysis completed

• Decision with Canada on final W0 • Used to make USGG2012/CGG2013

– Leveling for TN, AL, MS, LA to be completed– OPUS-DB conversion/points pulled– “Final” NA2011 values delivered to Geoid Team– Preliminary GPSBM2012 list and OPUS-DB lists sent

out to State Advisers Plus

Timeline & Coordination

• March– WI leveling adjustment completed– Final GPSBM2012 sent to State Advisers Plus– GEOID12 developed

• April– NGSIDB pulled to ensure values from NA2011 (and

GPSBM2012) correctly reflect the database– NA2011 & GEOID12 released– Final NA 2007 => NA2011 conversion in OPUS-DB