The important factor of mortality occmring along the Labrador 

 Coast (evidenced by the small and variable survival rates from C to 

 the Grand Banks) probably is related to stranding and melting. 

 Stranding can be attacked through examination of the departure from 

 normal of the barometric pressure gradients producing onshore winds. 

 Melting can be attacked through examination of the departure from 

 normal of the barometric pressure gradients producing offshore winds 

 and through a study of water-borne heat supplied to the Labrador 

 Current by the West Greenland Curjent in the northern part of the 

 Labrador Sea. This latter may be deduced from the heat transport 

 of the West Greenland Current passing Cape Farewell the summer 

 before tlie bergs reach the Grand Banks region. 



Any forecast formulae which are based on transportation facilities 

 alone, such as the methods developed by Smith ** in 1926 and by Schell ^ 

 in 1950, must remain rough approximations until modified to include 

 the four factors discussed above, namely, the departure from average 

 of the number of bergs calved from the glacier, the departure 

 from average mortality in the journey from area A to area B, the 

 departure from average of the number of bergs stranding along the 

 Labrador coast and the departure from average melting during that 

 part of the journey. Mensurable possible indices of some of these 

 factors exist but they have been measured an insufficient number of 

 times to permit evaluation of the relative importance of the different 

 factors, or even the validity of the supposed indices. A more detailed 

 treatment of them is deferred pending the accumulation of additional 

 data. 



SUMMARY 



1 . The circulation in the Grand Banks region has been discussed on 

 the basis of dynamic topographic charts resulting from three surveys 

 of the area made during the 1950 ice season. 



2. The volume of flow and mean temperature of the Labrador Cur- 

 rent at three selected sections in the Grand Banks region has been 

 determined for each of the three surveys made in 1950 and discussed 

 with respect to the results of earlier occupations of these sections. 

 Tentative normal seasonal variation curves have been presented for 

 volume of flow and mean temperature of the Labrador Current at 

 each of the three sections. 



3. The location of the northern boundary of Atlantic Current water 

 found during the three surveys made in 1950 has l)een discussed with 

 respect to the strength of the Labrador Current as measured and the 



' Smith, Edward H. "The Marion expedition to Davis Strait and Baffin Bay, Arctic Ice." U. S. Coast 

 Guard Bull. No. 19, pt. 3, pp. 180-189 (1931), Washington. 



» Schell, I. I. "On foreshadowing the severity of the iceberg season south of Newfoundland." Unpub- 

 lished paper read before the Thirty-first Annual Meeting of the Section of Oceanography of the American 

 Qeophysical Union, May 1950. 



92 



