Geoscience Reference
In-Depth Information
Figure 2.10.
Mean surface salinity (psu) for winter (adapted from Arctic Climatology
Project,
1997
, by permission of NSIDC, Boulder, CO).
the reference salinity, it has a negative freshwater component. The same basic idea
holds for calculating freshwater storages, ST, where in this case the salinity S refers
to the salinity of the storage term in question:
ST
FW
= ST
T
(1 - S/34.8)
(2.2)
Focusing on the major terms, river runoff to the Arctic Ocean, representing net
precipitation over the terrestrial Arctic drainage, is estimated at about 3,200 km
3
.
Note that the terrestrial drainage is much larger in area than the Arctic Ocean that
it empties into. Although the Arctic Ocean gains about 3,300 km
3
of freshwa-
ter from precipitation over the ocean itself, this is partly countered by evapora-
tion, leaving an oceanic net precipitation input of about 2,000 km
3
. As the atmo-
sphere loses water through the excess of precipitation over evaporation over both
