 |
| Titel |
Warming of waters in an East Greenland fjord prior to glacier retreat: mechanisms and connection to large-scale atmospheric conditions |
| VerfasserIn |
P. Christoffersen, R. I. Mugford, K. J. Heywood, I. Joughin, J. A. Dowdeswell, J. P. M. Syvitski, A. Luckman, T. J. Benham |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1994-0416
|
| Digitales Dokument |
URL |
| Erschienen |
In: The Cryosphere ; 5, no. 3 ; Nr. 5, no. 3 (2011-09-09), S.701-714 |
| Datensatznummer |
250002599
|
| Publikation (Nr.) |
 copernicus.org/tc-5-701-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| Hydrographic data acquired in Kangerdlugssuaq Fjord and adjacent
seas in 1993 and 2004 are used together with reanalysis from the NEMO ocean
modelling framework to elucidate water-mass change and ice-ocean-atmosphere
interactions in East Greenland. The hydrographic data show that the fjord
contains warm subtropical waters and that fjord waters in 2004 were
considerably warmer than in 1993. The ocean reanalysis shows that the warm
properties of fjord waters in 2004 are related to a major peak in oceanic
shoreward heat flux into a cross-shelf trough on the outer continental
shelf. The heat flux into this trough varies according to seasonal exchanges
with the atmosphere as well as from deep seasonal intrusions of subtropical
waters. Both mechanisms contribute to high (low) shoreward heat flux when
winds from the northeast are weak (strong). The combined effect of surface
heating and inflow of subtropical waters is seen in the hydrographic data,
which were collected after periods when along-shore coastal winds from the
north were strong (1993) and weak (2004). The latter data were furthermore
acquired during the early phase of a prolonged retreat of Kangerdlugssuaq
Glacier. We show that coastal winds vary according to the pressure gradient
defined by a semi-permanent atmospheric high-pressure system over Greenland
and a persistent atmospheric low situated near Iceland. The magnitude of
this pressure gradient is controlled by longitudinal variability in the
position of the Icelandic Low. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|