Temporal variability of mass transport in the Canary Current

Hernández‐Guerra, Alonso; Machín, Francisco; Antoranz, Ana; Cisneros-Aguirre, J.; Gordo, C.; Marrero-Díaz, Ángeles; Martínez, Ana Cristina Lahuerta; Ratsimandresy, A. W.; Rodríguez-Santana, Ángel; Sangrà, Pablo; López-Laazen, F; Parrilla, Gregorio; Pelegrí, Josep Lluís

doi:10.1016/s0967-0645(02)00092-9

Cited by 48 publications

(25 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previous studies of the Canary Current through the Canary Islands suggest a relatively high variability of the same order of magnitude as the mean flow. Hernández‐Guerra et al [2002] using expandable bathythermograph sections, from Gran Canaria Island to the African coast for 2 years every 2 months show that the easternmost branch of the Canary Current deviates on the order of 1.4 Sv from the mean flow. Hernández‐Guerra et al [2003], using a 4‐year current mooring in the Lanzarote passage, find that the deviation of the Canary Current is 1.1 Sv.…”

Section: Inverse Box Model Calculationsmentioning

confidence: 99%

Canary Current and North Equatorial Current from an inverse box model

et al. 2005

View full text Add to dashboard Cite

The large‐scale Canary Basin circulation is estimated from a box inverse model applied to hydrographic data from a quasi‐synoptic survey carried out in September 2003. The cruise consisted of 76 full depth CTD and oxygen stations. Circulation is required to nearly conserve mass and anomalies of salinity and heat within layers bounded by neutral surfaces. It permits advective and diffusive exchange between layers and an adjustment of the Ekman transport and the freshwater flux divergences. The Canary Current at the thermocline layer transports a net mass of 4.7 ± 0.8 Sv southward north of the Canary Islands from the African coast to 19°W. It is divided into a northward circulation at a rate of 1.1 ± 0.5 Sv between the African coast and Lanzarote Island and a southward transport of 5.8 ± 0.6 Sv. It transports North Atlantic Central Water and organic matters advected offshore by the filaments protruding from the upwelling system off northwest Africa. At 24°N, the Canary Current feeds the North Equatorial Current that transports a mixture of North and South Atlantic Central Waters westward. In the intermediate layer a southwestward flow of 1.2 ± 1.1 Sv transports Mediterranean Water to the Subtropical Gyre, though the highest salt flux is transported by a meddy. Oxygen distribution and mass transport suggest a northeastward deep flow of a water mass colder than 2.2°C consisting of diluted Antarctic Bottom Water. The heat and freshwater divergences and the average dianeutral velocity and diffusion between the sections and the African coast are negligible.

show abstract

Section: Inverse Box Model Calculationsmentioning

confidence: 99%

Canary Current and North Equatorial Current from an inverse box model

et al. 2005

View full text Add to dashboard Cite

show abstract

“… Hernández‐Guerra et al [2002] estimated the mass transport in the thermocline layer from XBT data in the Lanzarote Passage. They estimated the mass transport every two months for two years using a θ/S relation from historical CTD data.…”

Section: Variability In Mass Transportmentioning

confidence: 99%

“…Particular effort was made during the CANIGO project (Canary Islands Azores Gibraltar Observations) [ Parrilla et al , 2002] to improve our understanding of the physics, biogeochemistry, and paleoceanography of the portion of the EBC that flows through the channel between the island of Lanzarote and the African coast (hereafter Lanzarote Passage, Figure 1) [ Hernández‐Guerra et al , 2001, 2002, 2003; Knoll et al , 2002; Machín et al , 2006].…”

Section: Introductionmentioning

confidence: 99%

“…Results from these observations, together with hydrographic and XBT cruises, gave a fairly comprehensive new picture of the circulation at the eastern boundary. The water masses found in the passage had a mean annual mass transports of −0.8 ± 1.1 Sv for NACW, +0.1 ± 0.4 Sv for AAIW and −0.05 ± 0.09 Sv for MW [ Hernández‐Guerra et al , 2001, 2002, 2003; Knoll et al , 2002]. After the CANIGO experiment, measurements in the Lanzarote Passage were continued with just one mooring representative of the whole passage [ Hernández‐Guerra et al , 2003].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Nine years of mass transport data in the eastern boundary of the North Atlantic Subtropical Gyre

et al. 2010

View full text Add to dashboard Cite

[1] One of the longest current meter time series in the Lanzarote Passage in the eastern boundary of the North Atlantic Subtropical Gyre has been used to determine and quantify the 9-year mean transport, the inter-annual and seasonal mass transport variability for the three water masses present in the area. Results show North Atlantic Central Water (NACW) flowing southward in the upper levels with a mean mass transport of −0.81 ± 1.48 Sv, Antarctic Intermediate Water (AAIW) flowing northward at intermediate levels with a mean transport of +0.09 ± 0.57 Sv and Mediterranean Water (MW) flowing southward in the deep part of the passage with a mean transport of −0.05 ± 0.17 Sv. Harmonic and wavelet analysis show the presence of a seasonal pattern in the passage for the three water masses. A maximum southward transport in winter and spring has been observed for the NACW followed by a minimum in summer and fall. Near zero values during winter and spring are found for AAIW, with a maximum northward value in summer and a negative value in fall, when this water mass reverses its flow. MW has a similar seasonal pattern to NACW. The vertical structure in the Lanzarote Passage can be approximated by four significant oscillatory modes which cumulatively explain 86.4% of the variance. The strong transport fluctuation found at the seasonal and inter-annual timescales demonstrates that the Eastern Boundary Current transport has a strong impact on meridional overturning estimates, thus indicating that to understand Meridional Overturning Circulation variability, these transport estimates at the eastern Atlantic margin are necessary.

show abstract

“…This is presumably linked to reversals in the main flow, which allow the presence of a northward flow from Cape Blanc to Cape Juby, diverting westwards at this latitude (Pelegrí et al in press). These flow diversions are more frequent during late fall and winter, when trade winds are weaker, but are produced sporadically year-round (Navarro-Pérez & Barton 2001, Hernández-Guerra et al 2002, and might be responsible for much of the organic matter inputs into the region.…”

Section: Epipelagic Plankton Respiration and Organic Carbon Fluxes Inmentioning

confidence: 99%