ker det iskolde Vand ved Bunden til Tærskelen mellem 
Grønland og Island; søndenfor er Varmegrader ved Bunden. 
Det er til et Niveau af c. 300 Favnes Dyb, at det iskolde 
Vand rækker op ved Grændsen mod Atlanterhavet. 
Den isotherme Flade for 0° ligger i Nordhavet paa 
temmelig forskjellig Dybde paa de forskjellige Steder. I 
Grønlandshavet og i Østhavet er der Kuldegrader allerede i 
Overfladen. Deres Øst- og Syd-Grændse angives ved Iso- 
thermen for 0° paa Kartet Pl. XVI.  Østenfor og sønden- 
for denne Linie ligger det varme Vand i de øvre Lag. 
Dets horizontale Begrændsning sees paa Kartet Pl. X XV, 
dets verticale paa Snittene Pl. IX til XV. I den søndre 
Del af vort Nordhav række, 1 de øvre Lag, Varmegrader 
over hele Strækningen fra Danmarkstrædet til Norge. Jo 
længere man kommer nordover, desto mere indsnevres 
Bredden af det varme Vandlag. Allerede noget nordenfor 
Jan Mayen er den vestre halve Bredde iskold, og kun den 
østre har Varmegrader. Fra 74° Bredde er Bredden 
betydelig indskrænket og bliver stadig mindre, indtil det 
varme Vand ophører ved Nordvestspidsbergen. I Østhavet 
holder derimod Bredden sig temmelig jevn og stor. 
Den Dybde, til hvilken Varmegraderne naa, er 1 Al- 
mindelighed noget større ude i Havet end inde ved Ban- 
ken, og 1 end højere Grad er dette Tilfældet med Isother- 
men for — 1° (Den sænker sig i det søndre Bassin dybt 
ned mod dets Midte, i det nordre ligger dens Indsænkying 
henimod den østre Skraaning. «For tydeligere at vise dette 
Forhold har jeg paa Kartet Pl. XXIX afsat en bred 
skygget Linie, der gaar gjennem de dybeste Punkter af 
Isothermerne for — 1°, Paa Pl. XXVI er afsat Isother- 
mernes verticale Fordeling, projiceret paa en Meridian langs 
den østlige Rand af Nordhavet. Mellem Spidsbergen og 
Nordkap er sat et Grændsesnit over Beeren-Hiland, og fra 
Stad til Shetland et lignende, 1 hvilke Isothermerne ere 
optegnede i Verticalsnit. Ellers ere kun Bundtemperatu- 
rerne paa Bankernes Skraaninger benyttede, og Linierne 
indpassede efter Verticalsnittene og Isothermkarterne for 
de forskjellige Dybder. Man vil gjenkjende Virkningen af 
Landkulden i de øvre Lag. Sondenfor Vesteraalen (69° 
N. Br.) ligge Isothermerne 09 til 5° meget tæt sammen. 
Den følgende Tabel, hvis Tal ere tagne efter Profilet, viser 
Isothermernes Dybde ved Banken og deres Maximums- 
Dybde ude i Havet for 09 og for — 1° for de forskjellige 
Breddegrader. 
— in a single locality perhaps a little over — the crest 
of the Wyville-Thomson Ridge. The Iceland-Feroe Ridge 
lies higher. In Denmark Strait, the ice-cold water at the 
bottom reaches, so to speak, the threshold between Green- 
land and Iceland; farther south, water above 0° occurs at 
the bottom. It is to a level of close upon 300 fathoms 
from the surface, that the ice-cold water rises up at the 
boundary towards the Atlantic, 
The isothermal surface for 0° lies in the North Ocean 
at very different depths in the various localities. In the 
Greenland Sea and the Barents Sea 02 
occurs The limit to the east and 
south is indicated by the isotherm for 0° in the maps, 
Pl. XVI. To the east and south of this line, the warm 
water occurs in the upper strata. Its horizontal limit 
is shown in the map, Pl. X XV, its vertical in the sections, 
Pls. IX to XV. In the south part of the North Ocean, 
temperatures above 0° extend over the upper strata through- 
out the whole tract, from Denmark Strait to Norway. The 
farther north you go, the less becomes the breadth of the 
Even a little to the north of Jan Mayen, 
water below 
at the surface even. 
warm water. 
half the breadth — the western — consists of ice-cold 
water, the eastern only exhibiting degrees above 09%, From 
lat. 74° N, the breadth becomes considerably diminished, 
and steadily lessens, till, off the north-west coast of Spitz- 
bergen, the warm water altogether disappears. In the 
Barents Sea, on the other hand, the breadth keeps com- 
paratively equal and considerable. 
The depth down to which a temperature above 09 
is found to reach, is generally somewhat greater out at sea 
than close to the bank; and this refers in a still higher 
degree to the isotherm for — 1° It sinks in the southern 
basin to a great depth towards the middle; in the north- 
ern, its lowest point lies towards the eastern declivity. In 
order: to illustrate this relation with greater distinctness, I 
have drawn on the map, Pl. X XIX, a broad, shaded line 
passing through the deepest points of the isotherms for —1°. 
Pl. XX VI shows the vertical disposition of the isotherms — 
projected on a meridian — along the eastern margin of the 
North Ocean. Between Spitzbergen and the North Cape, I 
have traced a boundary-section, passing over Beeren-EKiland, 
and another from: Stad to Shetland, in which the isotherms 
are shown in vertical sections. With this exception, the bot- 
tom-temperatures only, on the slopes of the banks, have 
been used, and the lines made to agree with the ver- 
tical sections and the maps of isotherms for the different 
depths. The effect of the land-cold will be seen in the 
upper strata. South of Vesteraalen (lat. 69° N) the isotherms 
for 09 to 5° lie very close. The following Table, in which 
the figures have been taken from the profile, gives the 
depths of the isotherms on the bank and their maximum- 
depth out at sea for 0° and — 1° on the different latitudes. 
