Definition of Seasonal Ice Zone does not match that given in the literature

[andypbarrett]

The current definition of Seasonal Ice Zone is

an area of ocean that extends from the permanent ice zone to the boundary where winter sea ice extent is at a maximum; here, sea ice is present only part of the year; this zone primarily consists of first-year ice.

This is confusing and takes a few readings to understand. I also wonder if we should be thinking in terms of "permanent" sea ice cover.

Definitions in the literature

the area between the minimum and maximum seasonal ice limits plus the region of the ice margin that is significantly affected by the ice-ocean boundary.

From Wadhams, 1986: In Untersteiner Geophysics of Sea Ice

A more recent definition by Roach et al (2024), gives a more pragmatic definition based on the observational record

the extent of sea ice between the seasonal minimum and seasonal maximum extent limits

It seems that this definition is the simplest.