PHYSICAL OCEANOGRAPHY OF THE GULF OF MAINE 



659 



water that had been cooled near shore moving out from the land and at the same 

 time sinldng, to develop a shelflike intrusion into the warmer water of the center of 

 the bay. The profiles also suggest that the coldest water was produced even closer 

 in to the coast line than the innermost of the two stations, and that the whole column 

 was colder than 0° next this sector of the coast at about the end of January, down 

 to a depth of 10 to 15 meters. 



In 1925 the southern side of Massachusetts Bay had experienced its mini- 

 mum temperature for the winter and had commenced to warm again by the last 

 week in February, when the mean temperature of the surface (1.65°) was nearly 1° 

 higher than it had^been two weeks earlier, with a corresponding rise in mean bottom 



STaTions 



Fig. 84.- 



•Temperature profile running from the Marshfleld shore out into Massachusetts Bay, February 6, 7, and 27, 1925. 

 The broken curve is the isotherm for 2° on February 24 



temperature from 0.95° to 1.68°. On the 24th the whole surface of the bay was 

 close to 2° in temperature, a regional uniformity illustrated by readings of 2.2° a mile 

 or two off Gloucester, in the one side of the bay, with 2° to 2.1° in the central parts 

 and 2.3° near Provincetown (station 5) in the other side. The offshore drift of water, 

 chilled next the Plymouth shore, had also slackened, if not entirely ceased (fig. 84) . 



The vertical distribution of temperature off Provincetown (Fish Hawk station 5) 

 on February 24 is interesting because the bottom reading was the highest (2.34°) 

 recorded for any level at any of these late February stations. A 40-meter salinity 

 of about 33 per mille at 40 meters there, contrasted with 32.7 to 32.8 per mille in the 

 central part of the bay, shows that some inflow through the bottom of the channel 



