HR: 1330h
AN: G43B-02    [Abstracts]
TI: Relating Tide Gauge Records of Sea level Change to Local Vertical Motions
AU: * Snay, R
EM: Richard.Snay@noaa.gov
AF: NOAA's National Geodetic Survey, 1315 East-West Highway / Room 8813, Silver Spring, MD 20910 United States
AU: Cline, M
EM: Mike.Cline@noaa.gov
AF: NOAA's National Geodetic Survey, 1315 East-West Highway / Room 8813, Silver Spring, MD 20910 United States
AU: Dillinger, W
EM: william.h.dillinger@noaa.gov
AF: NOAA's National Geodetic Survey, 1315 East-West Highway / Room 8813, Silver Spring, MD 20910 United States
AU: Richard, F
EM: rick.foote@noaa.gov
AF: NOAA's National Geodetic Survey, 1315 East-West Highway / Room 8813, Silver Spring, MD 20910 United States
AU: Hilla, S
EM: steve.hilla@noaa.gov
AF: NOAA's National Geodetic Survey, 1315 East-West Highway / Room 8813, Silver Spring, MD 20910 United States
AU: Kass, W
EM: bill.kass@noaa.gov
AF: NOAA's National Geodetic Survey, 1315 East-West Highway / Room 8813, Silver Spring, MD 20910 United States
AU: Ray, J
EM: jim.ray@noaa.gov
AF: NOAA's National Geodetic Survey, 1315 East-West Highway / Room 8813, Silver Spring, MD 20910 United States
AU: Rohde, J
EM: jim.rohde@noaa.gov
AF: NOAA's National Geodetic Survey, 1315 East-West Highway / Room 8813, Silver Spring, MD 20910 United States
AU: Soler, T
EM: tom.soler@noaa.gov
AF: NOAA's National Geodetic Survey, 1315 East-West Highway / Room 8813, Silver Spring, MD 20910 United States
AB: We relate local rates of relative sea level change to ITRF2000 vertical velocities via a simple function involving a regional rate of sea level change G and the components Vx, Vy, and Vz of a constant 3-D velocity vector referred to the X-, Y-, and Z-axis, respectively, of ITRF2000. Using rates from 36 tide gauges spanning the U.S. coast (Atlantic, Gulf, and Pacific as well as the coast along southern Alaska, Hawaii, Kwajelein, Guam, and Bermuda) together with ITRF2000 vertical velocities for 38 continuously operating GPS reference stations (CORS), each of which is located within a few tens of kilometers of one of these 36 tide gauges, we estimate that G = 1.8 +/- 1.1 mm/yr, Vx = 2.3 +/- 0.9 mm/yr, Vy = -0.2 +/- 1.1 mm/yr, and Vz = -6.0 +/- 1.4 mm/yr, where uncertainties represent standard errors. The misfit between these local sea level rates and the corresponding ITRF2000 vertical velocities at their associated CORS has a WRMS value of 1.6 mm/yr. This misfit is due primarily to uncertainties in the CORS-derived vertical velocities because of the relatively short history of these sites (2 - 9 years). Our results imply that a few years of GPS data from a CORS located along the U.S. coast may be used to predict the rate of local sea level change with a standard error of 1.6 mm/yr. Conversely, a few decades of tide gauge data may be used to predict local ITRF2000 velocities with this same level of accuracy. Moreover, rates of relative sea level change can also be related to vertical velocities expressed in any other spatial reference frame whose velocities are related to ITRF2000 velocities by a transformation as is the case with the realization of the North American Datum of 1983 that is known as NAD 83 (CORS96).
DE: 1208 Crustal movements--intraplate (8110)
DE: 1229 Reference systems
DE: 1243 Space geodetic surveys
DE: 1247 Terrestrial reference systems
DE: 1255 Tides--ocean (4560)
SC: Geodesy [G]
MN: 2005 Joint Assembly