An Analysis of Salinity Stratification in San Juan Channel

Abstract

The Salish Sea in an estuarine circulation system comprising of the Fraser River in Canada and the Pacific Ocean. Stratification in the San Juan Channel is variable by two very distinctly different means in the north and in the south of the channel. This study examined the variability of tidal forcing on the San Juan Channel. NANOOS archived data, 2004-­‐2013 for the north channel and 2008-­‐2013 for the south channel along with 2014 PEF data, was used to analyze salinity data values. A subsample was taken from the salinity data depending on the resulting standard deviations. Every subsample was then classified by being either flood-­‐spring, flood-­‐neap, ebb-­‐spring, ebb-­‐neap using a dyadic relationship. In the southern channel, there was a large saline intrusion at depth due to a Pacific Ocean exchange from tidal forcing during a flood cycle. The salinity in the northern part of the channel had variability that could not be explained through tidal height. When the standard deviations were very small, all four classifications were found to have very strong mixing throughout the water column in both the north and south of the San Juan Channel.