When scientists talk about the cryosphere, they mean the places on Earth where water is in its solid form, frozen into ice or snow. Read more ...
Cryosphere Glossary
ice rind
a brittle, shiny crust of floating ice, formed on a quiet surface by direct freezing or from grease ice, usually in water of low salinity; thickness less than 5 centimeters (2 inches); easily broken by wind or swell, commonly breaking into rectangular pieces.