OCEANOGRAPHY IN THE GULF OF MAINE AND ADJACENT 

 WATERS IN SUPPORT OF ICNAF 



January 1968; January-February 1969 



by 



MELVIN LIGHT AND SCOTT J. HENDERSON' 



INTRODUCTION 



This is the second report on a series of oceano- 

 graphic surveys of Northwest Atlantic coastal 

 waters conducted by the U.S. Coast Guard in 

 cooperation with the Bureau of Commercial 

 Fisheries (BCF; now the National Marine Fish- 

 eries Service). These surveys were carried out 

 in support of a fisheries research program 

 planned by the International Commission for 

 the Northwest Atlantic Fisheries (ICNAF). 

 Whitcomb (1970) reported on two earlier surveys 

 (ICNAF Cruises 67-2 and 67-3) which encom- 

 passed the waters of the Mid-Atlantic Bight. 

 This report presents the physical oceanographic 

 data observed on two later surveys (ICNAF 

 Cruises 68-1 and 69-1) which included the Gulf 

 of Maine and adjacent waters (Figs. 1-3). Coast 

 Guard oceanographers and marine science tech- 

 nicians aboard the USCGC EVERGREEN 

 (WAGO-295) conducted ICNAF Cruise 68-1 

 (15-26 January 1968). ICNAF Cruise 69-1 

 (28 January-27 February 1969) was conducted 

 by Coast Guard and BCF personnel aboard the 

 BCF ALBATROSS IV. 



The purpose of these surveys was to describe 

 the physical and chemical environment of the 

 region to gain a better understanding of the 

 factors affecting the seasonal and annual dis- 

 tribution and abundance of living marine re- 

 sources. Shortly after each oceanographic cruise, 

 BCF and other ICNAF research groups con- 

 ducted groundfish surveys of the same areas. 



'U.S. Coast Guard Oceanographic Unit, Building 

 159-E, Xavy Yard Annex, Washington, D,C. 20390. 



PROCEDURES 



Oceanographic Sampling 



Oceanographic sampling procedures, sample 

 analyses, bathymetric and meteorological obser- 

 vation methods, and quality control procedures 

 employed during these two cruises were generally 

 the same as those described by AVhitcomb (1970). 

 Oceanographic parameters measured at each sta- 

 tion included temperature, salinity, dissolved 

 oxygen, and chlorophyll. Beginning with ICNAF 

 cruise 69-1, water samples were routinely an- 

 alyzed for nutrients. As on the previous two 

 ICNAF cruises, drift bottles and sea-bed drifters 

 were released for the AVoods Hole Oceanographic 

 Institution. Expendable bathythermograph 

 (XBT) casts were generally made midway be- 

 tween oceanographic stations. 



Rosette Mxilti- Sampler 



For the first time during a Coast Guard 

 oceanographic survey, a General Oceanics Rosette 

 Multi-Bottle Array sampler was used during 

 ICNAF Cruise 69-1 with the Salinity-Tempera- 

 ture-Depth ]\Ieasuring System (STD) to obtain 

 salinity samples and temperature measurements. 

 This sampler allowed for calculation of thermo- 

 metric depths for quality control of the STD 

 system. This device enables one or more of a 

 cluster of 12 Niskin sampling bottles to be trig- 

 gered and their deep-sea thermometers (installed 

 on every other bottle) to be reversed upon com- 

 mand from a deck control unit via the electrical 

 conducting STD cable. Because of the config- 

 uration of the A-frames and oceanographic 



