Blended sea level anomaly fields with enhanced coastal coverage along the U.S. West Coast.

We form a new data set of fields of sea level anomalies by combining gridded daily fields derived from altimeter data with coastal tide gauge data. Within approximately 50-80 km of the coast, the altimeter data are discarded and replaced by a linear interpolation between the tide gauge and remaining offshore altimeter data. A 20-year mean is subtracted from each time series (tide gauge or altimeter) before combining the data sets to form the merged sea level anomaly data set. Geostrophic velocity anomaly fields are formed from the surface heights. Daily mean fields are produced for the period 1 January 1993 - 27 December 2014. The primary validation compares geostrophic velocities calculated from the height fields and velocities measured at four moorings covering the north-south range of the new data set. The merged data set improves the alongshore (meridional) component of the currents, indicating an improvement in the data set.