76 MARION EXPEDITIOX TO DAVIS STRAIT AND BAFFIN BAY 



a current band about 25 miles in widtli at an average rate ot 11 miles 

 per day. Off Fiskernses the water on the outer side of the current 

 again diverges in a narrow band about 15 miles in width and with a 

 velocity of 6 miles per day finally reaching across to the American 

 side of Davis Strait. The Marion found the current to run at 13 

 miles per day just off Godthaab but a short distance farther north 

 there was less dynamic tendenc}^ toward movement, suggesting a gen- 

 eral slackening and expansicm near the latitude of Sukkertoppen.'^'' 

 The northern terminus of the ice and current at Sukkertoppen is 

 probably due somewhat to the broadening of the continental shelf of 

 Little Hellefiske Bank, which tends to scatter the current and hold 

 back the ice. Our hydrographical survey indicates that icebergs in 

 the current will be carried northward along the west Greeidand coast 

 at the average rate of 15 miles per day, or in one month travel from 

 Cape Farewell to Sukkertoppen. 



According to these calculations icebergs travel much faster along 

 the west Greenland coast than they do along the Lal)rador side or, 

 according to previous scanty information, than they do along the 

 east Greenland coast. At the same time it should be remarked the 

 current along west Greenland is narrow, and unless a berg remains 

 within its bounds it will not follow this drift. The boundary be- 

 tween the main current and the main body of water to the west of the 

 latter is sharply defined, and since it is unlikely that a berg will keep 

 within such limits because the disturbing factors, such as the effect 

 of sea ice, of coastal promonotories, of cacliments. of gales, etc., we 

 may assume that many east Greenland bergs are carried inshore, to 

 strand. Avhile many others scatter out from the outer side of the cur- 

 rent. In the latter case they come into a sort of dead water where 

 they will disintegrate eventually without having made any material 

 progress one way or the other. Only at two points, at Cape Desola- 

 tion and near Fiskerna?s, is there any branching of the ice, and even 

 there such a tendency is slight. Bergs which follow such offshore 

 dispersals lose speed very rapidly and wind along tortuous trails. 



It should be noted that the positions of bergs as sighted by the 

 Marion expedition along west Greenland are all practically within 

 the bounds of the cui'rent. and places where our dymanic map shows 

 no current, those areas were for the most part berg free. 



The conditions under which one particular berg w^as sighted by the 

 Marion off Godthaab afford instructive evidence as to the behavior 

 and distribution of east Greenland bergs, supporting the conclusions 

 first reached from the dynamic current map. As we stood out into 

 Davis Strait from Godthaab Fjord, a medium-sized berg was sighted 

 dead ahead, distance 20 miles from the coast. We noticed on ap- 

 proaching that the course had to be altered continuously to the left 

 in order to counteract an apparent set of the ship northward. The 

 depth of 60 fathoms at that spot indicated that the berg was either 

 grounded or at least that it extended downward very nearly to the 

 bottom so that it was difficult to escape the conclusion that a surface 



•'" In constructing a dynamic topograpbic map tlie motion on the chosen surface ( in the 

 case of fig. !!5), tiie sea surtace is compared with that on a phiue wliere tne water is at 

 rest. If the water, therefore, surface to bottom, is moving at the same or nearly the same 

 velocity, no basis of comparison is possible and the dynamic topographic map will show 

 no isobaths where in fact there is a current. There is of course tne possiljility such may 

 have been the condition in the vicinity of Sukkertoppen the first week in August, 1".)28. 



