摘要: This report of the ice program conducted during 1971 in the North American Arctic, the last of this series, was conducted by the Naval Oceanographic Office. Methods of collection and dissemination of ice data, ice forecasting, for... 展开 This report of the ice program conducted during 1971 in the North American Arctic, the last of this series, was conducted by the Naval Oceanographic Office. Methods of collection and dissemination of ice data, ice forecasting, forecast verification, and interpretation of satellite ice observations are discussed. Sea ice distribution in the eastern arctic was generally normal or slightly heavier than normal. Expected dates for escorted and unescorted entry into 5 selected eastern Arctic ports were forecasted. Conditions for escorted entry into 3 of these ports occurred as predicted. Escorted entry at the 2 remaining ports occcurred 1 to 9 days later than forecast. Conditions for unescorted entry also occurred as predicted at 3 of these ports. Unescorted entry was possible 6 days later than forecast at one port and 20 days earlier than forecast at the fifth port. Ice conditions in the western Arctic were heavier than normal for the third consecutive year, especially in the Bering Sea during spring. Ice conditions, based on aerial and satellite data in the eastern and western sectors of the Arctic and data observed over the Arctic Basin during 2 BIRDS EYE missions, are shown graphically. 收起