Typical sea ice types are shown here near the end of the winter season. Also shown is how often sea ice has been present at any location on the 26th February over the last 30 years. Based on the observations of sea ice extents and ice types over the last 30 years, this map shows how frequently sea ice has been present and what is the most likely predominant ice type and where. Sea ice is any form of ice that is found at sea and has originated from the freezing of seawater. The ice type gives an indication of the thickness of sea ice such as new ice, grey ice, grey-white ice, first year ice, and old ice. Ice represents a danger for navigation. Information on sea ice is essential in estimating transportation costs, and what type of vessel is appropriate. The map shows the typical sea ice types near the end of the winter season (February 26) and as well as frequency of sea ice on that date. The frequency of sea ice indicates how often sea ice has been present on February 26 over the last 30 years.