Cooperative Institute for Research in Environmental Sciences

Analysis of wintertime mesoscale winds around southeastern Greenland

Alice K. DuVivier and John J. Cassano

2014, Monthly Weather Review, Accepted pending revisions

Strong, mesoscale tip jets and barrier winds that occur over the ocean near southern Greenland have the potential for impacting ocean circulation, particularly deep convection. However, the variability in these wind patterns and how this variability might be important for driving ocean processes has not been investigated. The self-organizing map (SOM) technique was used to identify the range of winter (NDJFM) wind patterns represented in 10 m wind data from the ECMWF Interim Reanalysis (ERA-I) and from two regional simulations using the Weather Research and Forecasting (WRF) model at 50 km (WRF50) and 10 km (WRF10) resolutions. Previously identified wind patterns were found to span a range of possible manifestations with different implications for ocean forcing. WRF50 simulated patterns with strong barrier-parallel flow more frequently than ERA-I, and WRF50 also had faster coastal winds than ERA-I. The two WRF simulations had little significant difference in mean wind speed. However, larger differences were found for extreme events, though the sign and magnitude of the difference varies spatially and across the different types of wind patterns. As a result, the air-sea interactions and the impact on sea ice and the ocean during particular types of events is complex and not generalizable.