@article{discovery96866, volume = {39}, note = {{\copyright} Copyright 2009 American Meteorological Society}, publisher = {AMER METEOROLOGICAL SOC}, title = {Gap-Leaping Vortical Currents}, pages = {2665 -- 2674}, journal = {Journal of Physical Oceanography}, year = {2009}, month = {October}, number = {10}, issn = {0022-3670}, keywords = {WESTERN BOUNDARY CURRENT, POTENTIAL VORTICITY, COASTAL CURRENTS, UNIMAK PASS, FLOW, DYNAMICS, MOTION, VORTEX, TOPOGRAPHY, BARRIERS}, author = {McDonald, NR and Johnson, ER}, url = {http://dx.doi.org/10.1175/2009JPO4191.1}, abstract = {A one-parameter family of exact solutions describing the bifurcation of a steady two-dimensional current with uniform vorticity near a gap in a thin barrier is found. The unsteady evolution of source-driven flows toward these steady states is studied using a version of contour dynamics, appropriately modified to take into account the presence of a barrier with a single gap. It is shown that some of the steady solutions are realizable as large-time limits of the source-driven flows, although some are not owing to persistent eddy-shedding events in the vicinity of the gap. For the special case when there is zero net flux through the gap, numerical experiments show that the through-gap flux of vortical fluid increases with the width of the gap and that this flux approaches a steady limit with time.} }