242 
BULLETIN OF THE BUREAU OF FISHERIES 
31 
30 
29 
28 
O 27 
< 
« 26 
25 
24 
23 
22 
21 
20 
<=> 4 
0 
Considerable fluctuation in water temperature, characteristic of Milford Harbor 
and similar inshore waters is the result of changes in weather conditions and stage of 
tide. The daily and hourly fluctuations are at once apparent from Figure 25 which 
shows the maximum and min- 
imum temperature for each 
day together with the mean. 
Variations in the daily range 
of temperature amounted 
to from 1° C. to 11.5 ° C. 
The highest temperature in- 
variably occurred at the time 
of low water while the lowest 
temperatures were found near 
the time of high water when 
the greatest quantity of water 
had been brought in by the 
flood tide from Long Island 
Sound. The typical hourly 
changes in temperature that 
occur during a tidal cycle are 
shown graphically in Figure 
26 for several days in 1926. 
The highest water tempera- 
ture recorded by the thermo- 
graph during July and August 
was 31° C. and the lowest 
10.5° C. In the studies of 
thermal conditions it was 
found that exposure and 
flooding of the tidal flats in- 
crease greatly the exchange 
of heat between the water, 
land, and air and are respon- 
sible for the large fluctuations 
in temperature of the water. 
/ 
/ 
I 
r 
/ ' 
AUG. 4,1926 
JULY 23, 1926 / 
JULY 14, 1926 
/ 
JULY 2, 1926 
n. 
/V. 
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5 / 
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3 
L.V\ 
The salinity of the water 
in Milford Harbor depends 
upon two main factors, name- 
ly, the discharge of fresh water 
L W by the Wepawaug River and 
^ the inflow of brackish water 
from Long Island Sound. The 
distribution of salinity in the 
harbor is shown in Figure 27 for a series of observations that were made during flood 
tide on July 15, 1925.. During the summer the range of salinity was from 4.50 to 28.66 
9 10 
SALINITY 
2 3 4 5 6 7 8 
HOURS AFTER LOW WATER 
Figure 26.— Fluctuations in water temperature during tidal cycle, Milford Harbor 
