Impact of Resolution on the Representation of the Mean and Extreme Winds
along Nares Strait
Abstract
Nares Strait is the long and narrow strait bounded by steep topography
that connects the Arctic Ocean’s Lincoln Sea to the North Atlantic’s
Baffin Bay. The winds that blow along the strait play an important role
in modulating ice and water exports from the Arctic Ocean as well as in
helping to establish the Arctic’s largest and most productive polynya
that forms at its southern terminus. However, its remote location has
limited our knowledge of the winds along the strait. Here we use weather
station data from the region as well as 3 numerical models with
horizontal resolutions that vary from ~30km to
~2.5 km to characterize the wind field in the vicinity
of the strait. The strait has a width that varies from
~40km to ~100 km and as such the wind
field is typically ageostrophic and controlled by the pressure gradient
in the along-strait direction. We show that model resolution plays a
role in the representation of both the mean and extreme winds along the
strait through the ability to represent this ageostrophic flow. Higher
windspeeds occur in the vicinity of Smith Sound and are the result of a
left-hand corner jet. Kane Basin, the widest section of the strait, is
characterized by a pronounced zonal windspeed gradient that is the
result of the steep topography of the upstream Washington Land
peninsula.