  The center-of-mass dynamics of a vortex in the surface region of a
Bose-Einstein condensate is investigated both analytically using a variational
calculation and numerically by solving the time-dependent Gross-Pitaevskii
equation. We find, in agreement with previous works, that away from the
Thomas-Fermi surface, the vortex moves parallel to the surface of the
condensate with a constant velocity. We obtain an expression for this velocity
in terms of the distance of the vortex core from the Thomas-Fermi surface that
fits accurately with the numerical results. We find also that, coupled to its
motion parallel to the surface, the vortex oscillates along the direction
normal to the surface around a minimum point of an effective potential.
