(1) Here is a Global sea Ice Model (GIM_seaice_model) that is based on a spherical coordinate system and handles the north pole gracefully.
(2) J. Zhang has written a parallel sea ice model with a line successive relaxation (LSR) dynamics solver (Zhang and Hibler 1997) and, in collaboration with Dr. D. Menemenlis at JPL, has coupled the model to the MIT general ocean circulation model (MITgcm). Being semi-implicit, the LSR dynamics solver is particularly useful for high-resolution parallel simulation of ice motion, deformation, and ridging, without running into stability problems that may cause huge ice buildup.
(3) Our ice dynamics code using the alternating direction implicit (ADI) scheme (Zhang and Rothrock 2000) has been implemented in the GISS GCM ModelE.