Available surface drifter data are analyzed to determine the character
istics of the North Hawaiian Ridge Current (NHRC) and its relation to
the ocean circulation around the Hawaiian waters. The NHRC is found to
exist as a mean entity along the coasts of the Hawaiian Islands. It o
riginates as a northern branch of westward moving interior how and flo
ws coherently along the islands at an average speed of 0.10-0.15 m s(-
1). The NHRC veers westward at the northern tip of the Hawaiian Island
s, and its subsequent path is not influenced by the presence of the su
bmerged Hawaiian Ridge. This finding does not support the theory that
the NHRC is forced by westward propagating, baroclinic Rossby waves re
flecting off the Hawaiian Ridge. Using a 2 1/2-layer reduced gravity m
odel of the North Pacific, it is shown that the mean NHRC is due prima
rily to the mean rather than the time-varying wind forcing. The NHRC e
xists due to the imbalance between the interior Sverdrup transport and
the net southward transport, constrained by the presence of the Hawai
ian Islands. The path and transport of the observed NHRC are found to
be consistent with the flow pattern proposed by this theory.