Changes in the pool of Labrador Sea Water in the subpolar North Atlantic

Measurements of chlorofluorocarbon inventories during 1997–2003 allow the detection and quantification of significant changes in the formation rates of two modes of Labrador Sea Water (LSW): Upper (ULSW) and deep LSW, both here defined in fixed density intervals. Both modes contribute to the cold li...

Full description

Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Kieke, D., Rhein, M., Stramma, Lothar, Smethie, W. M., Bullister, J. L., LeBel, D. A.
Format: Article in Journal/Newspaper
Language:English
Published: AGU (American Geophysical Union) 2007
Subjects:
Labrador Sea
North Atlantic
North Atlantic oscillation
Online Access:https://oceanrep.geomar.de/id/eprint/5375/
https://oceanrep.geomar.de/id/eprint/5375/1/29_Kieke_2007_ChangesInThePoolOf_Artzeit_pubid7180.pdf
https://doi.org/10.1029/2006GL028959
Description
Summary:Measurements of chlorofluorocarbon inventories during 1997–2003 allow the detection and quantification of significant changes in the formation rates of two modes of Labrador Sea Water (LSW): Upper (ULSW) and deep LSW, both here defined in fixed density intervals. Both modes contribute to the cold limb of the Meridional Overturning Circulation. Results reveal that the lighter ULSW formed since the mid-1990s has started to replace the large pool of the deep LSW stored in the western North Atlantic. Formation of deep LSW was absent in 1997–2003. Formation of ULSW compensated for this absence during 1998/99 (7.9 Sv), but afterwards significantly declined to 2.5 Sv. The decrease of the overall LSW formation throughout 1997–2003 correlates with a declining eastward baroclinic mass transport between the centers of the subpolar and subtropical gyres since 1997, a warming of LSW, and a gradually decreasing North Atlantic Oscillation index after 1999.

Similar Items