GLOSSARY OF TERMS 



This selected glossary is limited to definitions helpful for an 

 understanding of this handbook. More extensive glossaries are 

 included in various Hydrographic Office publications. HO Study 

 No. 103, A Functional Glossary of Ice Terminology, has been pre- 

 pared in order to standardize ice terminology and to provide a 

 convenient means for describing ice features and related char- 

 acteristics. Refer also to Selected Bibliography, chapter 7, this 

 handbook. 



Ablation — Surface removal of ice or snow by evaporation. 

 A7'ctic Pack (Polar Pack) — The ice cc^^er of the north polar basin 

 or Arctic Sea (also called Arctic "Ocean"). 

 Barrier — The cliff ed edge of shelf ice. (See Shelf Ice.) 

 Bay Ice. — Fast, level ice formed in an embayment. 

 Belt — A relatively narrow band of sea-ice of any variety. 

 Berg — A large mass of land ice which has broken away from its 

 parent formation on the coast and either floats in the sea or is 

 stranded on a shoal ; a berg is tabular if derived from shelf ice, 

 irregular if derived from glacial ice. 



Bergybit — A medium-sized piece or cake of glacier ice, heavy floe, 

 or hummocky pack ice washed clear of snow and floating in the sea. • 

 Beset — Situation of a ship or small craft when so closely sur- 

 rounded by sea-ice that control is lost. 



Big Clearing — A large area of open water, other than a lead, en- 

 compassed by fields or floes of pack ice ; also polynya. 

 Bit — A single piece of brash or of ice less than two feet in diam- 

 eter. Note: compare with Glacon, Cake, Floe, and Block. 

 Blizzard — Snow storm in polar regions in which fine snow drifts 

 so high and thick that it is impossible to tell whether sky is clear 

 or clouded. 



Block — A small piece of ice ranging in size from 6 to 30 feet across. 

 Brash — Small ice fragments less than 6 feet across ; the wreckage 

 of other forms of sea-ice. 



Broken Ice — Sea-ice consisting of scattered cakes and floes cover- 

 ing five-tenths to seven-tenths of the sea surface. 



IX 



