Department of Physics, University of Alaska, Fairbanks, Alaska 99775-5920, USA.
Chaos. 2011 Mar;21(1):013111. doi: 10.1063/1.3555835.
The Arctic Ocean and sea ice form a feedback system that plays an important role in the global climate. The complexity of highly parameterized global circulation (climate) models makes it very difficult to assess feedback processes in climate without the concurrent use of simple models where the physics is understood. We introduce a two-dimensional energy-based regular network model to investigate feedback processes in an Arctic ice-ocean layer. The model includes the nonlinear aspect of the ice-water phase transition, a nonlinear diffusive energy transport within a heterogeneous ice-ocean lattice, and spatiotemporal atmospheric and oceanic forcing at the surfaces. First results for a horizontally homogeneous ice-ocean layer show bistability and related hysteresis between perennial ice and perennial open water for varying atmospheric heat influx. Seasonal ice cover exists as a transient phenomenon. We also find that ocean heat fluxes are more efficient than atmospheric heat fluxes to melt Arctic sea ice.
北冰洋和海冰形成了一个反馈系统，在全球气候中起着重要作用。高度参数化的全球环流（气候）模型的复杂性使得，如果不同时使用物理过程明晰的简单模型，就很难评估气候中的反馈过程。我们引入了一个二维基于能量的正则网络模型，来研究北极冰-海洋层中的反馈过程。该模型包含了冰-水相转变的非线性方面、非均匀冰-海洋格点内的非线性扩散能量传输，以及表面的时空大气和海洋强迫。对于水平均匀的冰-海洋层，第一个结果显示了在不同大气热通量下，常年冰和常年开阔水域之间的双稳性和相关滞后现象。季节性冰盖只是一种短暂的现象存在。我们还发现，海洋热通量比大气热通量更有效地融化北极海冰。
