132 DEPARTMENT OF THE NAVAL SERVICE 



8 GEORGE V, A. 1918 



C. Horizontal Distribution of Temperature. 



In the hope that more light might thereby be thrown on the subject, three maps 

 have been constructed, showing the distribution of temperature in the surface water 

 (fig. 20) and at depths of ten fathoms and thirty fathoms respectively (figs. 21 and 22). 

 As pointed out above, figure 20 shows an indication of an influx of warm surface 

 water, which passes along the south shore and then turns across the bay (see foot note 

 on page 131). If this represents a current in this direction, however, the deeper water 

 should be colder than on the other side, as it must come in from the cold Labrador 

 current, and we have already seen that the results both seasons tend rather the other 

 way. Figures 21 and 22 show no sign of such a circulation, but rather combine with the 

 four profiles to indicate a simple tongue of cold water up the middle of the bay. The 

 cold area on the slope of Grand Manan in the 1914 profile esjyecially supjwrts this. 

 There is nothing at ten fathoms corresponding in any way to the area of colder water 

 appearing at the surface of station X (8-46° surface temperature) and points east of 

 it, nor does the conformation of the shore appear to suggest any satisfactory explana- 

 tion. That proposed at the end of the previous section appears to be the only one at 

 present. The isolated area of warmer water east of Grand Manan (station II) in fig. 

 20 does not seem to be explicable on the basis of the present data either. The probable 

 position of the 10° C. isotlierm along the north shore is indicated by a broken line, 

 although, of course, there are not sufficient data to locate this properly. 



DEDUCTIONS FROM DATA OBTAINED EN ST. MARY BAY. 



From the data obtained in St. Mary bay (table II) a plan of the distribution of 

 temperature in the surface water of that bay has been drawn (fig. 23). It shows a 

 rather uniform arrangement with gradually increasing temperature as one passes up 

 the bay from Petit Passage, the shape of the isotherms suggesting that there may be 

 a current up each side with a reverse current down the middle. Immediately below 

 Petit Passage the effects of the tremendous tidal currents through that channel are 

 visible, producing a rather complicated arrangement of the isotherms, due apparently 

 to several interfering cross-currents. The arrangements of the water must, of course, 

 vary very greatly at different states of the tide and the fact that all the observations 

 must be taken at different times makes it improbable that the diagram represents such 

 a condition as ever exists at any one time. 



It has been thought worth while also to include a diagram representing a longi- 

 tudinal section of St. Mary bay (fig. 24), although it must be fully recognized that 

 such a profile, constructed from temperature data taken at the surface and the bottom 

 only, is of a very tentative nature. The figure shows gradual and apparently rather 

 uniform rise of temperature as one passes up the bay, just such as might be expected, 

 the colder area at the surface of station 15 being the only indication of the cross-cur- 

 rents suggested by the surface diagram (fig. 23). No doubt if temperatures at inter- 

 mediate depths had been taken, more might have been seen. The relations of the cold 

 water appearing at the bottom of stations 13 and 15 are shown by fig. 25, which repre- 

 sents a line carried down the bay from station 13 somewhat farther west than the line 

 in fig. 24. It is seen that this cooler water is spread out sideways from a layer which 

 probably approaches the surface about the mouth of the bay, and occupies almost the 

 whole depth at station 22. It will be noted that, the bay being rather shallow through- 

 out, the temperatures are all comparatively high. 



The bottom temperatures in the Annapolis basin (stations 26-33, table II) are 

 peculiar in being much lower in many cases (especially station 31) than any water 

 entering from the river (station 33) or any present in Digby Gut (station 25). 



SUMMARY. 



This set of observations is a continuation and extension of that made in 1914. 

 The stations have been selected in such a way as to form three transverse sections and 



