PHYSICAL OCEANOGRAPHY OF THE GULF OF MAINE 
633 
However, surface readings taken by the Halcyon to the eastward of Penobscot 
Bay early that August proved about 2° lower than the expectation. Bathers, too, 
reported the water unusually cold along the beaches throughout that summer, after 
offshore winds. This was corroborated by serial observations off Gloucester, which 
proved the whole column of water below the 30-meter level 1° to 3° colder in Au- 
gust, 1923, than it was three weeks earlier in the season even in the cold summer of 
1916, although the difference in date would suggest just the reverse. Depths greater 
than 40 meters were also 1° to 3° colder off Cape Elizabeth in 1923 than in any pre- 
vious August of record (fig. 68), notwithstanding the warm surface just mentioned. 
This statement would probably hold good for the inner part of the basin in general, 
also, as well as along the eastern coast of Maine, the relationship being similar near 
Mount Desert Island and off Mount Desert Rock (table, p. 635). 
It is probable that a summer colder than those of 1916 or 1923 comes very 
seldom in the Gulf of Maine, because winters so severe, and with so heavy a snow- 
fall, are exceptional (p. 697). 
The possibility that cyclic changes of temperature may take place in the gulf, 
with warmer or colder periods enduring over many years, must not be ignored; but 
nothing of this sort has been recorded there within historic times. 
The following comparative tables for representative localities will show in detail 
the annual differences in temperature summarized in the preceding pages. 40 
Annual differences in temperature 
MOUTH OF MASSACHUSETTS BAY 
Depth, meters 
1912 
10002 
July 10 
1913 
10087 
Aug. 9 
1914 
10253 
Aug. 22 
1915 
10306 
Aug. 31 
1916 
10343 
July 19 
1922 
10632 
Aug. 22 
1923 
Aug. 9 
0 - - - 
18.3 
16.7 
18.9 
16.1 
16.4 
18.1 
17.2 
20 - 
9.4 
10.6 
11.2 
10.5 
6.0 
9. 1 
9.0 
40 - - — 
6.6 
6.7 
6. 5 
8.0 
4. 1 
7.4 
5.5 
60 - — 
5.0 
5.4 
5.4 
6.7 
3.8 
5.6 
4.4 
80 - 
4.6 
5. 3 
4.8 
6.3 
3.7 
3.3 
100 
4.6 
5.2 
4. 6 
6.2 
3. 2 
120 - 
5.2 
4.5 
0.0 
3. 1 
140 
4.6 
5.9 
3.1 
WESTERN BASIN 
Depth, meters 
1912 
10007 
July 15 
1913 
10088 
Aug. 9 
1914 
10259 
Aug. 22 
1915 
10307 
Aug. 21 
0 
17.8 
19. 2 
20.0 
17.2 
20 - 
11.7 
12.6 
8.7 
6.4 
5.4 
5.2 
5. 6 
11. 5 
12. 5 
40 
8.0 
5. 8 
9.0 
60 - 
6.0 
4. 9 
7.0 
5. 7 
80_ - 
6.0 
4. 5 
100-- 
4. 7 
4. 4 
5.2 
5.2 
120 
4.6 
4.7 
140 
4. 6 
5. 9 
5. 3 
5. 3 
160 - 
4.6 
6.2 
5.9 
5. 7 
180 
4.6 
6. 3 
6. 5 
5. 8 
200 
4.6 
6.3 
6. 8 
5.9 
220 - 
4.6 
6.3 
7.0 
6.2 
240 — 
6.3 
7. 0 
6.4 
260 - - 
6.3 
7.1 
40 As the readings were not taken at the same levels at all the stations, or at as many levels as it is desirable to show here, it 
has been necessary in many cases to derive most of the values by interpolation. The temperatures are approximate, therefore, 
and are given only to the nearest tenth of a degree, Centigrade. 
