er Tilfældet (Pl. XIX). Under 609 Br. ved Wyville Thomson- 
Ryggen er Maximum af Tryk og et Temperaturmaximum paa 
Jv OD d ko) 
over 5°, Ved Spidsen vestenfor Stad er kun 29,1 Indbugtnin- 
gen udenfor Romsdalen med det hoje Tryk er 5°, under 66°— 
67° Br. er kun 3°, men udenfor Lofoten og Vesteraalen, 
hvor Trykket i Indbugtningen er højt, er mellem 5° og 4°. 
I Indbugtningen Syd for Beeren Eiland, hvor Trykket har 
et Minimum, er et Temperaturminimum af under 1”. Langs 
Spidsbergbanken, hvor den horizontale Bevægelse maatte 
foregaa tildels mod stigende Tryk, sker den i Virkeligheden 
langs Isobarerne med Nedstigning over Banken og højere 
Temperatur. Man sammenligne med Profilet Pl. XXVI, 
der viser disse Isothermernes op- og nedgaaende Bøjninger 
ved 300 Favnes Dybde. 
Wyville Thomson-Ryggens Dybde er omkring 300 
Favne. Over denne Ryg strømmer det varme og salte 
atlantiske Vand ind i Nordhavet, drevet af Tryk, der re- 
præsenteres, som vi have seet, ved Vindfladen, mod Nord- 
ost Færø-Shetland-Renden. Men 600 
Favne dyb. Det varme Vand drives hovedsagelig henimod 
Rendens sydøstlige Bred. Dets Underflade slæber en Del 
Vand med sig fra de dybere Lag. Dette erstattes derved, 
at der 1 de underste Lag strømmer Vand md langs Ren- 
indover denne er 
dens Bund fra Nordhavsbækkenet, og langs Rendens nord- 
vestre Bred — Færøbanken — imod det statiske Tryk. 
Virkningen heraf se vi i Temperaturens Fordeling. Iskoldt 
Vand dækker Rendens Bund helt op til 300 Favnes Dyb, 
og iskoldt Vand løfter sig langs Færøbanken til et endnu 
højere Niveau. (Profil VI, Pl. IX). Endvidere: Vandets 
Bevægelse langs den sydøstre Bred mod attagende Tryk 
løfter det op, og Isothermen for —1° 1 dette Profil bøjer 
sig op mod begge Sider, sænker sig ned 1 Midten. Hertil 
kan ogsaa den Omstændighed bidrage, at Vandets Bevæ- 
gelse i de højere Lag foregaar med en større Hastighed 
end i de dybere. Det hurtigere løbende Vand river det 
langsommere med sig, og dette maa erstattes — tomme 
Rum kunne ikke existere — fra neden. De her forklarede 
Principer for denne Art Reactionsvirkning, der oprindelig 
ere fremsatte af Professor Ekman 1 Stockholm, finde jevnlig 
Anvendelse 3 den følgende Redegjørelse. En Bevægelse 
mod mindre Tryk, altsaa under en Vinkel med Gradienten, 
der er mindre end en ret, vil have tilfølge — under ufor- 
andret Friction — en større Hastighed, og en raskere Be- 
vægelse opad. Den større horizontale Hastighed fremkalder 
ogsaa en raskere Sugning af de dybere Lag opad. 
Det Vand, som Polarstrømmen ikke sender ud gjennem 
Danmarkstrædet, faar sit Afløb gjennem Jan Mayen-Ren- 
den, langs Islandsbanken, Island-Færø-Ryggen og Færø- 
banken. I 300 Favnes Dyb kan dette Vand bevæge sig 
temmelig nær paa normal cyclonisk Maade. Efter sin Op- 
181 
increase, a downward tendency, with an increase of tem- 
perature, And such we see is actually the case (Pl. XIX). 
In lat. 60° N, at the Wyville-Thomson Ridge, occurs a maxi- 
mum of pressure and a temperature-maximum of more than 5°. 
At the salient point west of Stad, there is only 2°; in the 
recess off Romsdalen, with the high pressure, the temper- 
ature reaches 5°; in lat. 66°to67° N, it is only 3°; but off 
Lofoten and Vesteraalen, where the pressure in the 
recess is considerable, it reaches between 5° and 4°. 
In the recess south of Beeren Eiland, where the pres- 
sure has a minimum, there is a temperature-minimum 
of less than 1". Along the Spitzbergen Bank, where the 
horizontal motion should in part proceed against the pres- 
sure, it really follows the isobars, with a descent across 
the bank and a higher temperature. Compare with the 
profile Pl. XX VI, that shows these upward and downward 
bends of the isotherms in a depth of 300 fathoms. 
The depth of the Wyville-Thomson Ridge reaches 
about 300 fathoms. Over this ridge, flows into the North 
Ocean the warm and salt water of the Atlantic, impelled 
by pressure — which, as we have seen, is represented by 
the wind-surface — towards the north-east, along the Færoe- 
Shetland Channel. But this channel is 600 fathoms deep. 
The warm water is carried chiefly towards the south- 
easterly border of the channel. Its under surface carries 
along with it water from the lower depths. This is com- 
pensated by water pouring along the bottom of the chan- 
nel in the deepest strata from the basin of the North 
Ocean, and also along the north-western border of the 
channel — the Feroe Bank — against the static pressure. 
The effect of this is seen in the distribution of temperature. 
Ice-cold water covers the bottom of the channel as high 
up as 300 fathoms, and ice-cold water rises along the 
Færoe Bank to a still higher level (Profile VI, Pl. IX). 
Moreover, the motion along the south-eastern margin with 
diminishing pressure raises the water, and the isotherm 
for —1° in this profile rises towards either side and sinks 
in the middle. 
the motion of the water im the higher strata having a 
Possibly this is brought about im part by 
greater velocity than in the deeper. The water running with 
greater velocity carries along with it that flowing at a slower 
rate, and this has to be compensated a vacuum cannot 
exist — from below. The principles, expounded here, on 
which I base this kind of reaction (they were originally 
set forth by Professor Ekman in Stockholm) meet with 
frequent application in the following explanatory statement. 
A motion with decreasing pressure, or at an angle with the 
gradient less than a right angle, will be attended with the 
result — friction unchanged — of greater velocity and a 
more rapid upward motion. The greater horizontal velocity 
will also occasion more rapid suction upwards of the 
deeper strata. 
The water which the Polar current does not dis- 
charge by way of Denmark Strait, it sends through the Jan- 
Mayen Channel, along the Iceland Bank, the Iceland-Fzroe 
Ridge, and the Færoe Bank. Ata depth of 300 fathoms, this 
water can move very nearly in a normal cyclonic manner, 
