PHYSICAL OCEANOGRAPHY OF THE GULF OF MAINE 



661 



miles off Gloucester Harbor on the 9th (p. 994), where the surface reading was 1.67° 

 on the 6th in 1925. After the almost Arctic February of 1920, the Albatross found 

 the surface about 1.1° on March 1 on the run from Boston out to station 20050 at 

 the mouth of the bay, and the open gulf correspondingly low in temperature, as 

 described above (p. 522).''* 



It is also probable that the temperature of the water did not begin to rise in 

 1920 until after the first of March, instead of gaining heat from the middle of Feb- 

 ruary, as happened in 1913 and in 1925; but rising temperatures may be expected 

 in Massachusetts Bay by the last of February in all but the tardiest seasons. 



It would be interesting to compare the midwinter temperature of Massachusetts 

 Bay with that of the Bay of Fundy in the opposite side of the gulf. Unfortunately, 

 the winter data so far available do not sufficiently establish the relationship between 

 the two regions because they are for diS'erent years, except that there is no great 

 difference between them at the coldest season. 



Passamaquoddy Bay, tributary to the Bay of Fundy, seems also to correspond 

 closely to Cape Cod Bay in minimum temperature, its inclosed situation so exposing 

 it to climatic chilling that its surface falls close to the freezing point. Thus, Doctor 

 McMurrich's notes (p. 513) record a temperature of about — 1.7° at St. Andrews 

 from February 16 to March 3 in the very cold winter of 1916, compared with a 

 miuimum of —1.55° in Cape Cod Bay on February 6 and 7 of the more moderate 

 season of 1925 {Fish Hawk cruise 6, station 6A). WiUey (1921) also records -0.77° 

 at 20 meters depth in Passamaquoddy Bay on February 23 1917, which is about the 

 expectation for Boston Harbor and probably for the inner parts of Casco Bay and 

 of Penobscot Bay. 



Neither is the difference of latitude between the Bay of Fundy and Massachu- 

 setts Bay accompanied by more than a week's difference, or so, between the dates 

 when vernal warming becomes effective in the two regions. Thus, the trough of the 

 Bay of Fundy commenced to warm about the first of March in 1917 (Mavor, 1923), 

 and while Doctor McMurrich's plankton notes for St. Andrews do not show a rise 

 in temperature until the end of that month in 1916, this was even a more tardy 

 spring than 1920. 



"The surface of Massachusetts Bay is recorded as 3.3° on Feb. 24, 1920 (Bureau of Fisheries Document No. 897, p. 183); but 

 this is simply the quartermaster's record. 



