This is the first time that it has been possible to present a 

 Sj^Tioptic description of the temperature and salinity regime surface to 

 bottom for the east coast of the United States. Rathbun (I887) and 

 Parr (1933) have previously described and discussed the surface tempera- 

 tures along this same coastline for earlier periods. Bumpus, 1957 7 tias 

 tabulated the monthly and annual means of all the available surface 

 temperature data for the period of record. 



We are particularly indebted to the U. S. Coast Guard personnel 

 manning the lightships for their careful participation in this respon- 

 sibility which is in addition to their regular chores; to Mr. Edward 

 Green at Graxid Harbour^ Grand Manan; Mr. George Ferris at Woods Hole; 

 Mr. Steacy Hicks at Kingston, R. I., and the 12th Weather Squadron 

 USAF at Georges Shoal and Otis AFB. 



We are desirous of continuing the collection and publication of 

 these data on an annual basis. We should be glad to include data of 

 comparable nature f rem other locations were they available . 



This work was supported by the U. S. Fish and Wildlife Service 

 under Contract No. lU-19-008-2377 with the Woods Hole Oceanographic 

 Institution. 



Commentary 



We have attempted below in the commentary for each station to point 

 out the obvious features which characterize in general the hydrographic 

 conditions during the year 1956. Obviously the biological investigator 

 concerned with a particular group of plants or animals, or a more pre- 

 scribed area, may wish to look to the data for more details than we have 

 generalized here. 



Parr (1933) went into some detail about the reliability of estimat- 

 ing the bottom temperature at lightship positions along the Atlantic 

 Coast from the surface temperatures. He had no continuous records of 

 bottom temperature at these positions. We now have, for the first time, 

 a diagram of the surface and bottom temperature throughout the year 

 (Figure 2) along the string of lightship positions from Portland to 

 Savannah. 



The major feature which Parr did not discuss is the displacement 

 of the maximum bottom temperature to much later than the time of maxi- 

 mum surface temperature; from one to three months later at all loca- 

 tions from Diamond Shoals northward except Georges Shoals where the 

 water is always isothermal. Because the thermocline is so weakly 

 developed on the shelf south of Hatteras the time of maximum tempera- 

 ture is practically the same at the bottom as at the surface. 



