A modeling study of an Antarctica polynya event

作者：Morelli Sandra^*

来源：Meteorology and Atmospheric Physics, 2011, 114(1-2): 67-81.

DOI：10.1007/s00703-011-0157-5

An event of polynya at Terra Nova Bay (TNB), occurring from 15 July to 17 July 2006, is simulated by a recent version of the mesoscale Eta model. Simulation results and observational data describe the surface conditions during the period. The spatial and temporal structure of the atmospheric boundary layer in response to the warm area of the polynya is also investigated. Numerical experiments show that the latter influences significantly the wind intensity, the temperature and the specific humidity of the air over Terra Nova Bay. The significant heating of the low atmosphere results in a three-dimensional anomaly in the baric field, which extends far in the Ross Sea, embedded in the complex pressure field obtained by the Eta model also without taking into account the polynya. A turbulent kinetic energy plume, indicating turbulent mixing, and an increased vertical diffusion of horizontal momentum are also simulated over the polynya. The downward flux of high momentum air and the modified pressure gradient force change the wind speed at low level over TNB.

• 出版日期2011-10