Abstract
This study examines salinity barrier layers (BLs) in the eastern
tropical North Pacific in the region of the Salinity Processes in the
Upper ocean Regional Studies-2 field campaign. We utilize a high-
resolution numerical model to study BLs and their relationship to
frontal features and small-scale ocean variability, focusing on two
specific events. One is associated with a large outbreak of BL presence
near 7°N along 125°W. The other is a relatively isolated but persistent
BL that forms near 13°N, again along 125°W. In both cases we find that
the BL is proximate to a salinity frontal feature in which isohalines
tilt toward the fresh side of the front at its base. The BLs studied are
associated with divergent flow at the surface on the fresh side of the
front and convergent flow on the salty side. Tilting of the front is
invoked to explain this, with an additional mechanism involving a
vertical circulation which causes the base of the front to tilt
preferentially.