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| Titel |
Decadal Changes in Ventilation and Anthropogenic Carbon in the Intermediate Depths of the Arctic Ocean |
| VerfasserIn |
Balamuralli Rajasakaren, Emil Jeansson, Are Olsen, Toste Tanhua, Truls Johannessen |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250149112
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| Publikation (Nr.) |
 EGU/EGU2017-13432.pdf |
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| Zusammenfassung |
| We use transient tracer (CFC-12) observations from the GLODAPv2 data product to
investigate the decadal evolution of mean age and the amount of anthropogenic carbon (Cant)
in the intermediate depths (200 – 2000 m) of the Arctic Ocean. Applying the transit
time distribution (TTD) method, we find that ventilation has deepened in the upper
1600 m in the Eurasian Basin and Amerasian Basin from the 1990s to the 2000s.
Ventilation in the Eurasian Basin mainly takes place via advection of upper Polar
Deep Water (uPDW) and dense Atlantic Water (dAW) at about 500 – 1500 m. The
ventilation during the studies period may be connected to an observed increased
inflow of Atlantic Water, particularly from the Barents Sea Branch. Ventilation in the
intermediate depths of the Amerasian Basin is mainly in the Arctic Atlantic Water
(AAW) and dense Arctic Atlantic Water (dAAW) in both the Makarov and South
Canadian Basins and uPDW in the South Canadian Basin, while the West Canadian
Basin is more in a steady state. As a consequence of the ventilation in the Eurasian
Basin, Cant has increased by about 4-7 μmol kg−1 from 1987 to the 1990s, and by
about 6-9 μmol kg−1 from the 1990s to the 2000s. There is also an increase in
anthropogenic carbon in the upper 1750 m in the Amerasian Basin of about 10 μmol kg−1
from the 1990s to the 2000s. The Arctic Ocean Cant inventory for the intermediate
waters has significantly increased from the 1990s to the 2000s and the inventory for
the 2000s is calculated to be about 2 Gt-C (specific inventory ≈ 40 mol C m−2). |
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