Interannual Variations of Volume Transport in the Western Labrador Sea Based on TOPEX/Poseidon and WOCE Data

• Main Authors: Han, Guoqi, Tang, C. L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Meteorological Society 2001
• Subjects: QH301 Biology; Curl; Greenland; Labrador Sea; North Atlantic; North Atlantic oscillation
• Online Access: https://research.library.mun.ca/1889/; https://research.library.mun.ca/1889/1/Interannual_Variations_of_Volume_Transport_in_the_Western_Labrador_Sea_Based_on_TOPEXPoseidon_and_WOCE_Data.pdf; https://research.library.mun.ca/1889/3/Interannual_Variations_of_Volume_Transport_in_the_Western_Labrador_Sea_Based_on_TOPEXPoseidon_and_WOCE_Data.pdf; https://doi.org/10.1175/1520-0485(2001)031<0199:IVOVTI>2.0.CO;2

The interannual variations of volume transport in the western Labrador Sea are estimated using six years of TOPEX/Poseidon altimeter data and hydrographic data from a WOCE repeat section and a method based on the linear momentum equation in which the sea surface is the level of known motion. The interannual variation of the total transport in spring/summer has a range of 6.2 Sv (Sv ≡ 106 m3 s−1) and is positively correlated with the fall/winter North Atlantic Oscillation (NAO) index and wind patterns in the northwest North Atlantic. The total transport anomaly is decomposed into a barotropic and a baroclinic component. The interannual change of the barotropic transport is similar to that of the total transport, and is positively correlated with the fall/winter NAO index. The baroclinic transport anomaly, in comparison, has a smaller magnitude and the opposite sign. The authors conjecture that the deepened Icelandic low in high index years generates a strong cyclonic wind stress curl, which in turn creates a strong divergence and a large upward sea surface slope toward the Greenland coast, resulting in an intensified Labrador Sea circulation.