 Paper published in December 2000. * Corresponding author. Tel.: #1-603-646-2119; fax: #1-603-646-3856. E-mail address: christopher.naimie@dartmouth.edu (C.E. Naimie). Deep-Sea Research II 48 (2001) 501}518 On the geographic and seasonal patterns of the near-surface circulation on Georges Bank * from real and simulated drifters  Christopher E. Naimie*, Richard Limeburner, Charles G. Hannah, Robert C. Beardsley Dartmouth College, Hanover, NH 03755, USA Woods Hole Oceanographic Institution, MS 21, Woods Hole, MA 02543, USA Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada B2Y 4A2 Woods Hole Oceanographic Institution, MS 21, Woods Hole, MA 02543, USA Received 15 April 1999; received in revised form 10 November 1999; accepted 15 February 2000 Abstract We examine the near-surface circulation on Georges Bank by comparing data collected from satellite- tracked drifters in the real ocean and data computed for simulated drifters in a virtual ocean. The observed trajectory data set was obtained from drifters drogued at 10 m during the 1995}1997 US GLOBEC Northwest Atlantic/Georges Bank "eld program. The simulated drifter trajectories were computed based upon the seasonal circulation as predicted by the Dartmouth Circulation Model, using bimonthly clima- tological forcing. The observed and simulated drifter patterns indicate well-organized anticyclonic around- bank #ow on the northern #ank, Northeast Peak, and southern #ank throughout the year. The key to recirculation around the Bank is the seasonality of the northward #ow in the Great South Channel. Winter months are characterized by little northward #ow, while there is signi"cant northward #ow in the Great South Channel in summer. In late summer, both observed and numerical drifters indicate a minimum recirculation time on Georges Bank of roughly 40 days. The simulated drifter trajectories generally predict a seasonal climate consistent with the observed drifters, though the e!ects of weather events on the observed drifters are not captured by the numerical simulations.  2000 Elsevier Science Ltd. All rights reserved. 1. Introduction The primary objective of the long-term drifter component of the US GLOBEC Northwest Atlantic/Georges Bank program is to characterize the Lagrangian circulation on and around 0967-0645/01/$ - see front matter  2000 Elsevier Science Ltd. All rights reserved. PII: S 0 9 6 7 - 0 6 4 5 ( 0 0 ) 0 0 0 8 7 - 4