Abstract

As summer Arctic sea ice extent has retreated, the marginal ice zone (MIZ) has been widening and making up an increasing percentage of the summer Arctic sea ice. The MIZ is defined as the region of the ice cover that is influenced by waves, and for convenience here is defined as the region of the ice cover between ice concentrations of 15% to 80%. The MIZ is projected to become a larger percentage of the summer ice cover, as the Arctic transitions to ice free summers. We compare the processes of ice volume gain and loss in the ice pack to those in the MIZ to establish and contrast the relative importance of processes in the pack and MIZ , and the changes as the summer MIZ fraction and amplitude of the seasonal sea ice growth/melt cycle increases. We use an atmosphere-forced, physics rich sea ice-mixed layer model that includes a prognostic floe size distribution (FSD) model including brittle fracture and form drag.