OCEANOGRAPHIC CONDITIONS IN NORTHEASTERN 

 BAFFIN BAY DURING AUGUST 1969 



by 

 MARTIN J. MOYNIHAN ^ 



INTRODUCTION 



The USCGC SOUTHWIND occupied thirty- 

 six oceanographic stations in the waters of central 

 and northeastern Baffin Bay from 14 to 28 August 

 1969 as part of the International Ice Patrol's West 

 Greenland Glacier and Oceanographic Survey 

 (fig. 1) . This survey was part of a multiyear proj- 

 ect to investigate the tidewater glaciere and oceano- 

 graphic conditions along the western coast of 

 Greenland to determine the differences between 

 existing conditions and historical data as related 

 to the origin and drift of icebergs (Moynihan, 

 etal., 1970). 



Temperature data and water samples were col- 

 lected by Nansen casts. The resulting water sam- 

 ples were analyzed for salinity and oxygen 

 concentrations on board the USCGC SOUTH- 

 WIND. Salinity was determined on board using 

 an inductive salinometer. The conductivity values 

 obtained were converted to salinity by use of the 

 International Oceanographic Tables published 

 jointly by UNESCO and the National Institute of 

 Oceanography of Great Britain (1966). Dissolved 

 oxygen concentrations were determined by the 

 modified Winkler Method as described by Strick- 

 land and Parsons (1968). The resulting data were 

 processed later at the Coast Guard Oceanographic 

 Unit with a PDP-5 computer. 



The data presented in the Tables of Oceano- 

 graphic Data (Appendix A) are reproduced from 

 computer listings from the National Oceano- 

 graphic Data Center (Cruise Number 31-1529). 

 Anomalies of dynamic height in the listings were 

 computed by NODC; but all discussion of dy- 

 namic heights in this text are based on computa- 

 tions made at tlie Coast Guai-d Oceanographic 

 Unit. 



' U.S. Coast Guard Ooeanographlc Unit. BIdg. 158-B, Washing- 

 ton Navy Yard, Washington. D.C. 20390. 



In addition, grab samples and cores of bottom 

 sediments were obtained with an orange peel grab 

 and Phleger corer at selected stations in the fjords 

 seaward of glacier termini. The collection of these 

 samples was supervised by U. S. Naval Oceano- 

 graphic Office personnel. A preliminan- anlaysis 

 was conducted by Achstetter, et al. (1970), and 

 the remaining material is presently held at the 

 Geological Laboratory of the Naval Oceano- 

 graphic Office. 



DISCUSSION 



The circulation of Baffin Bay plays an impor- 

 tant role in the drift of icebei'gs from their parent 

 glaciers ou the western coast of Greenland to the 

 North Atlantic shipping lanes off the Grand 

 Banks. Smith (1931). Hawley. et al. (1941), and 

 Dunbar (1951) described a cyclonic circulation of 

 water in Baffin Bay and a similar drift of icebergs. 

 West Greenland Current Water enters from the 

 southeast through Davis Strait and water of polar 

 origin enters from the northwest through Lan- 

 caster. Jones and Smith Sounds. The southward 

 flowing Baffin Land Current along Baffin Island 

 and recirculation of some West Greenland Current 

 Water through the western side of Davis Strait 

 account for the outflow of water from Baffin Bay. 



Charts of dynamic topography (figs. 2 and 3) 

 prepared from" tlie USCGC SOUTHWIND's sur- 

 vey were used to depict the current patterns in 

 this area. A weak northward flowing current was 

 found near the Greenland coast and the general 

 southeastward drift found offshore is believed to 

 be the extreme eastern portion of the Baffin Land 

 Current. 



Remnants of the West Greenland Current were 

 found in the warm, saline (>1.0°C, >34.4%o) 

 layer between 250 and 800 meters on all sections. 

 A core of warm, high salinity water (>2.0°C, 

 >34.5%o) between stations 27 and 32 (figs. 6 and 7) 



