Sea Ice Modeling

Overview

Teaching: min
Exercises: min

Questions

• How Does Sea Ice Modeling work?

Objectives

Why is it important to model sea ice?

• Arctic sea ice extent is known to be decreasing due to Arctic Amplification, the effect that the poles are warming faster than the rest of the globe.
• Sea ice feeds back to other components of the climate system
• It has high albedo which has an impact on the Earth’s radiation budget
• It insulates the ocean from the atmosphere which impacts the exhanges of heat and moisture
• Can modify ocena circulation: Ice formation leads to salt flux to ocean; ice melt freshens the oceans

Sea Ice Models

The CESM2 sea ice component is called Community Ice CodE (CICE). Sea ice models have two primary components, some models have a 3rd component:

Dynamics

Force balance to determine the motion of the sea ice Wind stress, water stress, internal ice stress, Coriolis, and stress associated with sea surface slope Resistant to converence and shear

Thermodynamics and Radiative Properties

• Solves the vertical ice temperature profile: 8 sea ice thickness categories; 3 snow layers
• Determines the Vertical/lateral melt and growth rates
• Albedo
• Radiation
• Aerosol Depositing and cycling

Ice Thickness Distribution

Sub-gridscale parameterization to represent the spatial hterogeneity in ice

• Five ice categories
• PDF of the ice thickness evolution is solved
• Convergence, ice growth

Key Points