Daily Ice charts represent the best estimate of ice conditions at the valid time of the chart, based on an integration of data from a variety of sources, such as satellite, and ship and aircraft-based visual observations.
The charts describe ice concentration in tenths, ice types or stage of development and the form of ice. The boundary lines for different ice conditions, of particular importance to navigation, are determined by standards.
Ice information is presented in the Egg Code format and colour-coded using the World Meteorological Organization Standard.