14 



29,3"/o(i (the monthly mean was 26,3 — 32,4"/(d); at Aalborg it was during the same 

 period on an average 23,5 "/no (18,4 — 27, 7 "/do). At Ihe same time the monthly mean 

 temperature at Oddesund alternated between -^0,2" (Febr.) and 18,5° (July). At Aal- 

 borg it alternated belween -hl,4'' and 18,3 . The conditions characteristic of the 

 Limfjord are: a relatively high salinity, especially in the western part, a higher 

 summer temperature than in the open waters and the absence of a salter under- 

 layer with smaller alternations in the temperature. 



In the northern Kattegat, north of Lcies0, an active exchange takes place 

 between the surface-current and the under-current, which is the reason why the 

 salinity decreases considerably in both from north to south. As a rule the salinity 

 of the water streaming in at Skagen is between 30 and 35 "/oo, and the salinity 

 of the surface-water is ordinarily more than 25 "/oo. According to J. P. Jacobsen 

 the result of daily observations for 1880- 1905 shows, that the temperature and 

 salinity at Skagens Reef vary on an average in the following manner; 



Temperature Salinity 



M 2,5°— l(i,2° (mean 8,8") 27,3—31,4 



20 - 3° —15" 32,3—33,8 



38 - 4° —13,9° (mean 8,2°) 33,3—34,5 



At Ltcso Trindel the salinity, according to the charts in J. P. Jacobsen's 

 paper, is: at M. 23— 27"/no, at 10 M. 28— 29"/oo, at 20 M. 31— 32"/uo. 



In the eastern Kattegat the salinity of the surface water gradually de- 

 creases southward; not nearly so great an exchange however occurs here as in the 

 northern Kattegat. 



At Anholt's Knob the salinity is at M. 19— 23"'n.s at 10 M. 23— 25"/oo, at 20 M. 

 29—31 "/oo and at the same place the temperature alternates at the surface between 

 l,(r (mid. Febr.) and 17° (ca. 1. Aug.) at a depth of 28 M. between 4,2° and 13,5°, 

 at a depth of 40 M. between 4° and 11,5°. 



In the western Kattegat (Km.), which is only of small depth, the salt 

 bottom water is absent, except in Lseso Channel. At the lightship in Laese Channel 

 in 1880 — 94 the averages were: 



Temperature Salinity 



im-an minim. mean max. mean minim, mean max. 



M 2,2° (Febr.) ](),1° (July) 22,3 " oo 27,8"/oo 



24 - 3,4° (March) 13,9° (Aug., Sept.) 32.2"/oo 33,9"/oo 



The salt water coming through the Lseso Channel causes on mixing the water 

 in this region to become relatively saline, especially to the north and along the 

 coast of Jutland. In the greater part of the region the salinity at the bottom is 

 however not more than 25" i)o. 



In the Southern Kattegat and the waters east of Samso the salinity at the 

 surface is fairly uniform. In this area there is, especially in summer at a depth 

 of 10 — 20 M., a very distinct limit between an upper layer, which has ca. 20 "/oo 



