CLIMATE AND THE DISTRIBUTION OF MARINE ANIMALS 



315 



1915, 1923, and 1926. While the maximum 

 temperature recorded in this particular area was 

 as high (68°) for 1915 as for 1953, the average 

 for the summer of 1953 not only was higher than 

 any individual August reading for the earlier 

 years, with three exceptions, but was about as 

 much higher as comparable data for Boston 

 Harbor. 



Below-surface readings in the general offing of 

 Cape Ann in August show that, while those for 

 1953 ^ overlap somewhat those for 1912 to 1926 

 both in the upper 40 to 50 meters and at the 

 greatest depths sampled, the means for successive 

 strata were consistently higher for 1953, with an 

 overall difference averaging about 3.5° for the 

 water column as a whole (table 10). 



Table 10. — August temperatures off Cape Ann, in 1963 

 and in earlier years, to nearest degree 



[Area A, flg. 16. Temperature In °F.) 



Deptb (meters) 







15-20-.. 

 40-SO... 

 70-100. 

 110-130 

 150-170 

 180-274 



Mean 

 depar- 

 ture In 

 1953 



-1-3 

 -1-3 

 +3 

 -1-4 

 -1-5 

 -1-4 

 + 1 



' Partly from direct readings; partly as scaled from graphs for the individual 

 stations. 



It is especially instructive that the water in the 

 western side of the Gulf was between 1.5° and 

 5.7° warmer in 1953 than in 1926 (table 11), as the 

 mean water temperature for the warmest month 

 was almost precisely the same (67.2° and 67.3° F.) in 

 both summers in Boston Harbor. Evidently the 

 temperature at Boston for any one summer is not 

 a reliable index to conditions in the open Gulf at 

 that time of year, whether for the surface or for 

 the underlying watei-s. Consecjuently, mean water 

 temperatures for the warmest month as high as 

 67.3° to 68.9° in Boston Harbor in 1926, 1928, 

 1941, or 1944 do not necessarily mean that the 

 open Gulf was as warm in any one of these sum- 

 mers as it was in 1953, following 4 years when the 

 mean for the warmest month at Boston rose to 

 67.2° to 69.2° and the mean for the coldest 

 month did not fall below 35.9° to 37.8°. On 

 the other hand, it seems that the residual effects 



> Readings for 1912 to 1926 Uken tiy reversing thermometer, those tor 1953 

 by bathythermograph. 



of a winter colder than usual may be expected 

 to persist through the summer in the western 

 side of the Gulf in the underlying strata of water. 

 Such, at least, was the case in 1923, when the 

 mean temperature of the water in Boston Harbor 

 for the coldest month was 30.2°, following which 

 the temperature at 80 to 155 meters in the par- 

 tially enclosed sink off Cape Ann was 37.4° to 

 37.6° as late in the season as August 9, which 

 contrasts with 40.1° to 42.8° there between the 

 9th and 31st of that month in 1913, 1914, 1915, 

 and 1916 (4 stations). 



Table 11. — Water temperatures off Cape Ann in August 

 1926 and in August 1953 



[Ar«a A, flg. 16. Temperature in °F.] 



From the available information it appears likely 

 that the contrast between August temperatures in 

 1953 and in the earlier summers of record, for the 

 water colunm as a whole, was in general about as 

 we have outlined around the western and northern 

 slopes of the Gulf. In the southwestern part of 

 the basin, for example, near the 100-meter line 

 (area B, fig. 16; table 12), mean temperatures at 

 0, 40, 100, and 150 meters were 2.2° to 4.2° higher 

 at 3 stations on September 6, 1953, than on August 

 23, 1914. The summer of 1953 was relatively 

 warm, as is illustrated by the temperatures of the 

 water, surface to bottom, along the eastern part 

 of the coast of Maine and in the vicinity of Mount 

 Desert Island (area C, fig. 16; table 13). Here the 

 temperature was 1.5° to 3° higher on August 16, 

 1953, from the surface to near the bottom (37-40 



Table 12. — Water temperatures in southwestern part of 

 basin in August 191/, and in September 1953 



[Area B, flg. 16. Temperature In °F.] 



' 3 stations. 



