On the spatial distribution of high winds off southeast Greenland

The spatial distribution of barrier winds along southeast Greenland has been investigated through idealized modeling of unidirectional flow towards an isolated mountain. The regions of enhanced surface wind speed seen in previous studies are reproduced and shown to be primarily the result of promontories in the orography along the southeast coast (the maxima disappear in experiments without the promontories). Two mechanisms are proposed to explain these enhancements. Firstly, a reduction in pressure experienced by the flow as it passes a promontory results in an acceleration akin to that of easterly tip jets at Cape Farewell. Secondly, mountain waves observed along the southeast coast are accompanied by strong, low-level downslope winds in the lee of the promontories. Both mechanisms contribute to the simulated wind speed maxima.