84 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. /O 



VARIATIONS IN THE HEIGHT OF THE WATER OF THE COASTS OF THE 

 NORTH SEA AND THE BALTIC 



Another very interesting correspondence may be considered at 

 this point. In figure 42, we give at the bottom some curves which 

 show the variations in the mean height of the water for the year 

 at the different stations on the coasts of the North and the Baltic Seas. 

 For the years 1900 to 1909, the values of the uppermost of these 

 curves (for Esbjerg Korsor and Gjedser) are taken from Brehmer 

 in Ann. d. Hydr., May, 191 3. These tables do not, however, extend 

 back further than the year 1900. On the other hand Rosen (1903) 

 has published for the year ^1887 to 1910 tables for a number of 

 Swedish Baltic Sea stations. These show a well marked maximum 

 in all the stations for the year 1899. We have computed the mean 

 from all these Swedish results for the years 1898, 1899 ^^^ 1900. 

 The difference between 1900 and the two previous vears we have 

 employed to piece out in figure 42 the results of Gjedser oVer these 

 two years. The two lowest curves give the variations in the 

 height of the water at Swinemunde according to Brehmer m Ann. 

 d. Hydr., April 1914, page 207. The full drawn curve gives the 

 mean height of the water as indicated in Brehmer's column i. The 

 dotted curve gives the mean height of the water after correction 

 for tides (see Brehmer's column 17). The scale indicates centi- 

 meters and millimeters for these curves of the variations in the 

 height of the water is inverted. We see a well-marked maximum 

 in the years 1899 and 1903 and a well-marked minimum in 1901 

 and 1908. These are the same characteristic years of which we 

 have spoken above so often. A comparison between the curves 

 for the height of the water in the North Sea and the Baltic Sea 

 and the curves for the temperature differences in the Atlantic Ocean 

 show therefore a quite remarkable agreement in all years almost 

 without exception. In figure 43 we have extended this comparison to 

 the earlier years 1884 to 1898. Curve V shows the height in the water 

 in Swinemunde according to Brehmer (1914) curve VI, the mean 

 height of the water at the stations on the Swedish coast according 

 to Rosen (1903. p. 4). Curve I shows the temperature difference 

 of Petersen's stations 5 and 6 minus i and 2 ; curve III shows the 

 surface temperature at Liepe's station No. i, and curve IV gives 

 the air temperature in Hamburg. Correspondence between all 

 these curves is clear. The only considerable difference occurs in 

 the year 1895, when the height of the water should have showed a 

 minimum in order to correspond with the temperatures. There is 

 also some lack of correspondence in 1894. 



