The January 2013 Special Issue of Ocean Dynamics Journal is dedicated to papers discussed at the 3rd International Workshop on Modeling the Ocean (IWMO), which was held on June 6 9, 2011, in China. The subjects of papers in this special issue include four on data assimilations, hindcast and/or test forecast. Isobe and co-authors nest a high-resolution finite-volume model (FVCOM) within the Japan Coastal Ocean Predictability Experiment's (JCOPE2) reanalysis of the Kuroshio. Miyazawa and co-authors conducted hindcasts of the Kuroshio and coastal circulation south of Japan from January March of 2010 focusing in the Kii Channel where a strong sea surface temperature (SST) front is often observed and showed that the front can be realistically simulated. Shu, Ma, and Qiao reported observation of an ice floe drift in the Arctic Ocean from 8 to 19 August 2010 by the Chinese Arctic Research Expedition ship. Ezer and co-authors used a high-resolution POM model to study flow topography interactions near Caribbean coral reefs.