First-year ice

From Glossary of Meteorology

first-year ice

Sea ice that has not yet experienced summer melt.

First-year ice is distinguished from older ice primarily by having a higher salinity. Undeformed first-year ice differs from older ice in that it is smoother and lacks refrozen melt ponds. First-year ridges are distinguished by being larger, more angular, and more porous than multiyear ridges.