CuDibination. 



233 



wat.T ill tlu' Mo ami l.ysr Kinnls bad a tniiiicratuiv convsiKimlin-- 

 to tlu' avcraiiv aiiiiiial aliiiosplu'iic li'iniuMatm'f o( tlif place. Also 

 ill the latter lionl.-;, subiiiaiiiic ridiics prevent the warm bottom 

 water tVoiii pcnctratinir in, and. moreover, tlio snpply of fresh water 

 ill the winter is so ij-reat that the vertical current is prevented from 

 assumiii",' any lariie proportions. Tiie transmission of heat down- 

 wards takes place princiiially by conduction. A niaxiinum in the 

 autumn ami a mininiuni in the spring find their way ijradually 

 downwards, ami liiially an averaij'c is readied, wliicli coi'i-csponds 

 to the annual average atmospherie temperature.') The yicjerstad 

 Fiord must probably be classed with the ^lo and Lyse Fiords. 

 The bottom water is homoterniic (cf. Hydrography, p. 11). the 

 supply of fresh water is suflicient to prevent the wintei- cold iVuin 

 penetratinir down into the depths. 



The station yulitjelma, in the Vatnbynd river district, Jiad an 

 average fall of 1 097 mm. in the years 1896 — 1902, and the station 

 Graddis, in the Salt river district, during the same period had an 

 annual average of 533.-) According to Mohx,^) the annual average 

 temperature at Bodo is 4".l C. and at Ranen 3.5. On August 17th 

 1877, the Norwegian North Atlantic Expedition found that the 

 temperature in the Skjerstad Fiord at a depth of about 500 mtrs. 

 was 3.2. On April 4th 1900, I registered at the same depth 3".l5 C. 

 If one now considers these two atmospheric averages, it would 

 seem that 3.^; is a probable value for the annual aveiage tem- 

 perature of the air in the Skjerstad Fiord. 



If we, however, imagine the large basin of the Skjerstad Fiord 

 moved to the inner part of the Porsanger Fiord, and with the same 

 connections with the lattci- as it now has with the Salten Fiord, 

 we should certainly tind that the bottom temperature would be 

 considerably lower than that of the annual average of atmospheric 

 temperature in the inner part of the Porsanger Fiord. For, from 

 what has already been said, it will be seen that the supply of 

 fresh water at the latter place is not suftieient to preveait an 

 evening out of its salinity in the winter, thus allowing the winter 

 cold to exert its influence on deeper layers of water. 



In some of the lesser tiords adjacent to the Vest Fiord, I have 

 also noticed that the bottom temperature has been lower than the 

 annual average atmospheric temperature, which would imply that 

 somewhat of the Avinter cold has found its way downwards. 



Examples of this fact may be found in Rombakeu, Skjomen, 

 the Ggs Fiord etc. Such places excel in many arctic forms. These 

 tiords have already been referred to, and I would call attention to 

 what has been said about them in previous pages and also to PI. 

 19, where the curves YI, VII, YIII represent the conditions of 

 temperature in Skjomen, the Ogs and Skjerstad Fiords. The curves 

 for Skjomen and the Ogs Fiord are especially characteristic on 

 account of their slight bend, which is a sign of a uniform salinity. 



The temperature curves for Tranodybet, the Tys Fiord and 

 Oxsund are given so that compaiisons may be made, (PI. 19, 

 curves I, II, IV, V), all the curves are very much bent in the 

 upper layers, where there is great variation in salinity, but in the 

 layers where there is uniform salinity they become almost a straight 

 line. Curves III and IV, which represent the conditions of tem- 

 perature in March 1899 in the sea off Røst and in the Tys Fiord, 

 show plainly that a higher temperature prevails in the deeper 

 layers in the tiords than in the corresponding depths in the Nor- 



') Cf. Studier over uaturtbi-holdene i vestlandske fjorde, p. 4t;. 

 2j Cf. Nedbøi-iagtfagelsei- i Norge, aarg. VIII, ji. 12.5. 

 3) Kliinatabellei- for Xorge I. p. IS. 



wfoiaii Sea. .\s I iiave already stated, the rca.son for this is to 

 lie found in llie fact that such tiords as the Tys Fiord are of such 

 a formation as excludes the arctic bottom water from the .Nor- 

 wegian Sea, but gives admittance to the warm .\tlaiitic, waters 

 which fill the basins. Then too the fresh wafei' which Hows into 

 the tiord from the land, is sutticiently large in quantity from the 

 Bokn Fi(n'd to the Vest Fiord to prevent the wintei' cold from 

 penetrating downwards to any eoiisidei-alile depth. 



There is another tliiiii.'- wliicii one midit suppose to be, to 

 some extent, dependent upon the variation in downfall. 1 mean the 

 height of the water on the coa.st.s. 



From ..Vandstandsobservationer", published by „den norske 

 gradmaalingskommission" I have on pi. 20 drawn some curves, 

 which give the monthly average height of the water at Kabelvaag 

 and Vardø in the years 1882, 1884 and 1885. 



The measurements have been made with selfregistering instru- 

 ments at 0, 1, 2, 3 etc. hours after the moon's culmination and 

 from these results the average has been calculated. Taking it for 

 granted that the points have been unaltered, and that the instru- 

 ments in other respects too. have been quite reliable, one must be 

 able, by help of the data thus obtained, to form a wellfounded 

 opinion of the variations in the rise and fall of the water, in the 

 course of the year, on the northern coasts. A glance at the curves 

 (I — VI, PI. 20), will show that there is at any rate one tiling 

 which cannot possibly be accidental, the curves show a definite 

 tendency to a minimum in April. Similarly, too, a maximum can 

 be arrived at for the months November— January, while the re- 

 maining variations suggest accidental causes. 



On the same plate the curves representing the average monthly 

 downfall at Svolvær, which is situated near Kabelvaag and Vardo, 

 are given. Both these curves show a decrease during the first 

 months of the year up to May, in which month the year's minimum 

 downfall is reached. The Svolvær-curve shows a maximum in 

 November, and the Vardø-curve in October. Tliere is this point 

 of resemblance between the water-heights and downfall curves, that 

 they generally show a decrease during the first months of the year, 

 respectively up to April and May, but it cannot at all be said that 

 the decrease in heights is caused solely by the decrease in down- 

 fall. Of course the variations in downfall exert some influence on 

 the height of the coast water, but as regards the north of Norway, 

 it Avill easily be seen on comparing the curves that this influence 

 is by no means sufficient to account for the great differences in 

 height. It should be remembered that 1 cm. is taken as the unit 

 for the height, and 1 mm. for the downfall curves. 



At Svolvær, the amplitude of the curve representing the aver- 

 age, monthly downfall is 8.3 cm., the corresponding value at Vardo 

 is 5.3 cm. The observations made of heights have not been so 

 complete that it has been possible to calculate the normal average 

 for each month, but on the basis of the amplitudes of the Kabel- 

 vaag and Vardo curves, we get: — 



These figures show, with all desirable clearness, that the 

 variations in the course of the year are so considerable, that they 



30 



