From the very beginning the most intensive research and study has 

 been in physical oceanography, and by far the most satisfactory re- 

 sults have been obtained in this department. The method of reducing 

 the temperatures and salinities obtained fi'om water samples taken at 

 various depths below the surface to density in situ and then by means 

 of V. Bjerknes' formula computing the direction and velocity of the 

 surface current is fully described in Bulletin No. 14, 1926, entitled "A 

 Practical Method of Determining Ocean Currents", by Comdr. Ed- 

 ward H. Smith. In 1931 an oceanographic vessel was assigned to the 

 Ice Patrol Force and technique developed for the construction of cur- 

 rent maps at sea for the guidance of the patrol vessel. This method 

 of mapping ocean currents lias become one of the most useful tools of 

 the Ice Patrol. 



Observations of the upper air currents were early started both 

 by means of kites carr3dng recording meteorographs and by pilot 

 balloons. Important meteorological data were thus obtained, and at 

 the same time the causes and character of the famous Grand Banks 

 fog were thoroughly studied. The results of these studies are dis- 

 cussed in detail in the early Ice Patrol bulletins and also in an article 

 in the supplements to the Monthly Weather Review of the United 

 States Weather Bureau, 1914-17, Supplement No. 3, by C. S. Woods. 

 Meteorological data still play an important part in the patrol pro- 

 gram. The weather of the winter months in the region of Davis 

 Strait and Baffin Bay is used by the Coast Guard in making its 

 annual forecast of the number of bergs south of Newfoundland for 

 the following season. The data from the Major Marine Bulletin 

 of the Weather Bureau, together with weather reports from mer- 

 chant ships in the Ice Patrol area, are used by the patrol vessel to 

 construct weather maps twice a day. The resultant forecast is used 

 in planning the scouting for the next 2 days. 



Efforts were also made to develop a means for the detection of 

 icebergs ahead of vessels in fog or darkness. Following the work 

 of H. T. Barnes (1910, p. 131) the Ice Patrol, with the use of an 

 electrical resistance thermometer gi-aduated to one-hundredth of 

 a degree centigrade, attempted to record tj^pical temperature changes 

 upon approaching icebergs. Although the experiment was done 

 repeatedly under various conditions, no definite trend could be estab- 

 lished (A. L. Tliuras, 1915, Bulletin No. 3). The conclusions reached 

 were that the temperature effects of melting icebergs were less pro- 

 nounced than the minor fluctuations of the temperature in the sea 

 surface itself and therefore could not be used as a reliable index 

 of their presence and were investigated no further. It was also 

 suggested that bergs might be detected by a subsurface echo sound 

 deA-ice similar to the present sounding instruments. 



