There are various classifications for ice concentrations and the Canadians in particular have developed it almost into an art form with additional sub-classifications that include the age and type of ice.

Here in Antarctica the satellite imagery is less frequent and only the basic classification used, 1 to 4/10th's, very open drift ice, 4 to 7/10th's open drift ice, 7 to 9/10th's close drift ice and 10/10th's Fast ice.

I will leave you to decide what classification we forced our way through back into open water!