In order to use tidal gauges to reliably estimate global sea level changes, researchers have to successfully separate the components of shifting land heights and local sea level variability from any global trends. (globalwarmingsolved.com)
However, coastal sea level variability observed by tide gauges over the last few decades has been driven almost entirely by local winds. (usclivar.org)
Their method was able to explain about 70 percent of regional sea level variability on decadal time scales for the West Coast, about 80 percent for the East Coast, and about 45 percent for the Gulf Coast. (jpl.nasa.gov)