Open AccessUsing global positioning system‐derived crustal velocities to estimate rates of absolute sea level change from North American tide gauge records
Author(s) -
Snay Richard,
Cline Michael,
Dillinger William,
Foote Richard,
Hilla Stephen,
Kass William,
Ray Jim,
Rohde Jim,
Sella Giovanni,
Soler Tomás
Publication year - 2007
Publication title -
journal of geophysical research: solid earth
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2006jb004606
Subject(s) - tide gauge , geology , sea level , geodetic datum , glacier , atoll , post glacial rebound , geodesy , oceanography , climatology , physical geography , geography , geomorphology , reef
We identified 37 tide gauges; each located within 40 km of a geodetic station whose International Terrestrial Reference Frame of 2000 (ITRF2000) crustal velocity had been rigorously derived from continuous global positioning system (GPS) observations, spanning from 3 to 11 years. The tide gauges are located along the coasts of North America, Bermuda, Hawaii, and Kwajalein (in the Marshall Islands). We obtained the ITRF2000 crustal velocities by averaging values from six solutions; each produced by a team of investigators acting, essentially, independently of the other teams. We then applied crustal velocities to convert rates of relative sea level change to rates of absolute sea level change. In a sample containing 30 sites, we found that the mean rate of absolute sea level change equals 1.80 ± 0.18 mm/yr in the 1900–1999 period. The scatter about the mean for individual sites in this sample is characterized by a (weighted) RMS value of 0.85 mm/yr. This scatter primarily reflects the uncertainty associated with derived crustal velocities. The remaining seven sites, i.e., five sites on the Pacific coast of Alaska, one on Dauphin Island (Alabama), and one on Kwajalein (an atoll in the Pacific Ocean), experienced relatively low rates of absolute sea level change. We hypothesize the low rates in Alaska are caused by ongoing melting of mountain glaciers and ice masses near the stations, while the low rates found for Dauphin Island and Kwajalein remain unexplained.