Abstract
Relationship between synoptic forcing and polynya formation in the Cosmonaut Sea: 2. Regional climate model simulations
Relationship between synoptic forcing and polynya formation in the Cosmonaut Sea: 2. Regional climate model simulations
David A. Bailey
Cooperative Institute for Research in Environmental Sciences/Program in Atmospheric and Oceanic Sciences, University of Colorado,
Boulder, Colorado, USA
Amanda H. Lynch
Cooperative Institute for Research in Environmental Sciences/Program in Atmospheric and Oceanic Sciences, University of Colorado,
Boulder, Colorado, USA
Todd E. Arbetter
Cooperative Institute for Research in Environmental Sciences/Program in Atmospheric and Oceanic Sciences, University of Colorado,
Boulder, Colorado, USA
In part I of this series [
Arbetter et al., 2004
], a relationship was found in the observations between synoptic atmospheric systems and polynya formation in the Cosmonaut
Sea region of Antarctica. In this study, we use a regional coupled atmosphere-sea ice model to investigate the role of atmospheric
forcing of the polynyas in this area. The model successfully simulates both latent and sensible heat polynyas which are found
in the region. In particular, a deep-ocean polynya is formed coincident with the passage of an atmospheric synoptic scale
system. The divergence in the sea ice is found to be highly correlated with the atmospheric divergence. We conclude that the
initial formation of a polynya can be caused by the interaction of the atmospheric synoptic scale and the continental katabatic
wind regimes. While we cannot directly evaluate the role of the ocean using the present model simulations, we performed experiments
with different levels of prescribed basal heat flux. These experiments highlight a polynya which could be initiated by the
winds and maintained by the oceanic heat. This leads to the concept of a wind-driven sensible heat polynya, not typical of
other deep-ocean polynyas such as the Weddell polynya of the 1970s.
Received 26
February
2003;
accepted 23
February
2004;
published 24
April
2004.
Citation: Bailey, D. A., A. H. Lynch, and T. E. Arbetter
(2004),
Relationship between synoptic forcing and polynya formation in the Cosmonaut Sea: 2. Regional climate model simulations,
J. Geophys. Res.,
109,
C04023,
doi:10.1029/2003JC001838.