Daniel R Roman, National Geodetic Survey, HQ, Silver Spring, MD, United States, Xiaopeng Li, DST at NGS, Geosciences Research Division, Silver Spring, MD, United States; NOAA National Geodetic Survey, Silver Spring, MD, United States, Dana J Caccamise II, NOAA's National Geodetic Survey, San Diego, CA, United States and William A Stone, NOAA's National Geodetic Survey, Santa Fe, NM, United States