Modeling the Mechanisms for the Formation and Maintenance of the Weddell Polynya

这项拟议的工作涉及区域耦合大气环流模式的开发和应用，目的是阐明启动，维持和终止威德尔Polynya -威德尔海冬季海冰覆盖范围内的大面积开放水域的机制。 在1974年至1976年的高度上，冰穴的面积超过25万平方公里。本研究将使用的完全连接模式由大气行星边界层模式、包括积雪影响的海冰模式和三维海洋环流模式组成。 一个通量耦合器通过传递能量、质量和动量的相关通量将三个模型连接起来。 的细尺度功能的冰间湖将被建模的高分辨率版本的模型，将嵌套在较低的分辨率网格的大规模的域versions.The基本启动机制的威德尔Polynya被认为是温暖的深水（WDW），这是夹带到威德尔海从它的起源在南极绕极流的表面。 通常情况下，这种温暖的水（只有在南极标准下才是温暖的：它的温度在0到+1摄氏度之间）被更冷但含盐量更少（因此更轻）的威德尔冬季水表层保持在大约300米的深度以下。 偶尔，据推测，这种情况会打破;大气/海洋动力学消除了寒冷的表层，使WDW不仅融化了现有的冰，而且阻止了新冰的形成。 最终，WDW的热库被耗尽，并重新建立冷的表面层。 本研究的预期结果是定量确定不仅特征的时间演变的冰间湖，而且其特征的复发间隔，空间尺度，其连接到威德尔海的底部地形。 它是一种区域性气候事件，通过影响世界海洋深层水和底层水的形成和分布速率而产生全球性后果。

This proposed work concerns the development and application of a regional coupled general circulation model for the purpose of elucidating the mechanisms that initiate, maintain, and terminate the Weddell Polynya - a large area of open water within the winter sea ice cover of the Weddell Sea. This polynya was prominently seen in satellite-based passive microwave imagery, and at it height, from 1974 to 1976, exceeded 250,000 square kilometers in size.The fully linked model that will be used in this study is composed of an atmospheric planetary boundary layer model, a sea ice model that includes the effects of a snow cover, and a three dimensional ocean general circulation model. A flux coupler connects the three models by passing the relevant fluxes of energy, mass, and momentum among them. The fine-scale features of the polynya will be modeled on a high resolution version of the models that will be nested within the lower resolution grid of their large-scale domain versions.The basic initiating mechanism of the Weddell Polynya is thought to be the surfacing of Warm Deep Water (WDW) which is entrained into the Weddell Sea from its origins within the Antarctic Circumpolar Current. Normally this warm water (which is warm only by antarctic standards: its temperature is between 0 and +1 deg Centigrade) is kept below depth of about 300 meters by a colder but less saline (hence lighter) surface layer of Weddell Winter Water. Occasionally, it is speculated, this condition breaks down; the atmosphere/ocean dynamics remove the cold surface layer and allow the WDW not only to melt the existing ice, but keep new ice from forming. Eventually the WDW heat reservoir is exhausted and a cold surface layer is reestablished. The expected results of this study are a quantitative determination not only of the characteristic time evolution of the polynya, but also its characteristic recurrence interval, spatial scale, and its connection to the bottom topography of the Weddell Sea. It is a regional climatic event that has global consequences by affecting the formation and distribution rate of deep and bottom water thought the world ocean.