Paper 18 



VARIATIONS IN THE POSITION OF THE SHELF WATER FRONT OFF THE 

 ATLANTIC COAST B E T iJ E E M GEORGES BANK AND CAPE ROMAIN IN 1976 



John T . Gunn 



INTRUDUCT ION 



Dup to the tendency of forage oroanismsy and thus pelagic fish 

 stccksr to De associated with the convergence zone of ocean 

 frontS/^ knowledge of temporal and spatial variations of the Shelf 

 Water front position can be imoortant to fishery scientists. 

 Because the Shelf Water front may extend to the bottom over the 

 continental shelf^ there is also the possibility of an effect on 

 oenthic ana demersal species. It is anticipated that a better 

 understanding of the interaction of different species with ocean 

 fronts also may lead tc more efficient fishing efforts. 



This reoort is a product of a monitoring effort using infrared 

 satellite imagery which records thermal features of the sea 

 surface. Previous reports (Ingham 1976; Gunn 1978) have dis- 

 cussed front variations from June 1973r when data first became 

 availabley through 1975. This report will discuss the data for 

 1976 and its comparisons with previous years. 



DATA 



The basis of this study is the Experimental Gulf Stream Analysis 

 Charts' (Fir*. 18.1)y drawn fron the best infrared NOAA satellite 

 image of the week or/' if large yaps occur on daily charts due to 

 clouds or observational limits/' a composite of several partial 

 images. These charts show the position of the surface thermal 

 boundaries between the following oceanic features: Shelf Water/ 

 Slope Water/ Gulf Stream/ and warm and cold core Gulf Stream 

 eddies . 



Atlantic Environmental Groups National Marine Fisheries 



Service/ NOAA/ N ar r aga ns e t t / RI 02882. 



"Proouced by Environmental Sciences Group/ National 

 mental Satellite Service/ NOAA/ Washington/ DC 20233. 



Env i ron- 



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