A method for estimation of equivalent-volume ice thickness based on WMO egg code in absence of ridging parameters

When calculating equivalent-volume ice thickness along a vessel's projected route for the purpose of ice resistance estimation, information on both undeformed ice (level ice) and deformed ice (mainly ridges) is needed. Level ice information can be obtained from egg code-based ice charts in form of World Meteorological Organization (WMO) ice thickness ranges. Ridging parameters are sometimes available in ice charts as a supplement to the egg...