Greenland Patrol

The Greenland Patrol was a United States Coast Guard operation during World War II. The patrol was formed to support the U.S. Army building aerodrome facilities in Greenland for ferrying aircraft to the British Isles, and to defend Greenland with special attention to preventing German operations in the northeast. Coast Guard cutters were assisted by aircraft and dog sled teams patrolling the Greenland coast for Axis military activities. The patrol escorted Allied shipping to and from Greenland, built navigation and communication facilities, and provided rescue and weather ship services in the area from 1941 through 1945.

Earth's atmospheric circulation pattern requires westerly meteorological observations for prediction of weather conditions to the east. Weather observation stations in Greenland improved the accuracy of weather forecasting for the Atlantic Ocean and northern Europe for tactical advantage in the battle of the Atlantic and European theatre of World War II. Greenland had been part of the Danish colonial empire since 1814. Greenland appeared relatively unprotected following German occupation of Denmark on 9 April 1940. The Allies of World War II became concerned about the possibility of Axis military bases on Greenland. The cryolite mine at Ivittuut was a strategically important source of flux for electrolysis of aluminum ores by the Hall–Héroult process for aircraft production.

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