Interesting ice extent maps from 1901 and beyond

[LRC1962]

9. Need to consider ice quality besides ice quantity.

Quality not quantity of ice is the issue. Those old maps I suspect showing open ice where show areas that could be sailed though. In todays satellite era I think that the images would show then as ice filled based on 15% or more ice coverage. On top of that even the old 5 plus year old ice is alot thinner then years ago and in very poor condition. WUWT generally likes to treat all old ice the same as all old ice. As another poster has indicated about the condition of glaciers, The ice cores taken 30 years ago were for the most part solid very thick cores. Now cores taken from the same area are very much thinner and have the consistency of Swiss cheese.
Not only are we loosing ice very fast in area the quality is getting so poor that in the right conditions it will disappear very fast.