Exploring the spatial variation of tides for seafloor mapping data corrections

Senior thesis written for Oceanography 445

[author abstract] Acquisition of high definition hydrographic survey data has made several advancements in correcting for errors during signal acquisition. This potential error is associated with vessel position, ship motion and the changing speed of sound through the water column. However, until significant improvements occur in the vertical accuracy of GPS, the change in vertical distance of the survey vessel from the sea floor due to the constantly changing tides remains a source of error that is addressed during the post processing of hydrographic data. An accurate representation of the sea floor is critical in monitoring geomorphic processes as well as for the safety of navigation. This study used a specially designed pressure sensor array to collect tidal data near Seattle, WA in Puget Sound, and geostatistical analysis to determine the spatial scale of variability in tides. The results of this research validate the importance of collecting fine scale tide data in coastal areas with high tidal influences and offer an affordable option to collect this valuable data.

University of Washington School of Oceanography