New global drifter data set available

Pazan, Stephen E.; Niiler, Peter

doi:10.1029/2004eo020007

Cited by 32 publications

(19 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lutjeharms and van Ballegooyen, 1984;Boudra et al, 1989;Matano, 1996) all show the decisive influence of the bottom topography on the path of the Agulhas Return Current. Suggestions that the meanders so caused will persist as a wave of diminishing amplitude to the east (Pazan and Niiler, 2004) have still to be proven.…”

Section: Agulhas Return Currentmentioning

confidence: 99%

Three decades of research on the greater Agulhas Current

Lütjeharms

2007

Ocean Sci.

View full text Add to dashboard Cite

Abstract. The greater Agulhas Current has been shown to be a key link in the global thermohaline circulation and an increased understanding of this current system is therefore of more than just local interest. Knowledge on the Agulhas Current system has in fact increased enormously over the past 30 years. This review covers some aspects of what has been learnt on the northern and the southern parts of the Agulhas Current proper and their influence on the waters and circulation of the adjoining continental shelf. It also discusses the Natal Pulse and new information that has been gained on how it is triggered and what influence it has. It deals with the Agulhas retroflection, the shedding of Agulhas rings and the movement and characteristics of these rings that contributes to the meridional overturning circulation of the global ocean. The Agulhas Return Current forms part of the final outflow of the system and current knowledge on that current is appraised. The sources of the Agulhas Current have been a controversial subject for many years and this dispute continues. This is described and discussed, based on what information has been gained from research over the past three decades. Building on what is currently known, some suggestions are given on the most important remaining knowledge gaps and how these could most efficaciously be filled.

show abstract

Section: Agulhas Return Currentmentioning

confidence: 99%

Three decades of research on the greater Agulhas Current

Lütjeharms

2007

Ocean Sci.

View full text Add to dashboard Cite

show abstract

“…To evaluate such a flux, we performed an identical analysis using a mean velocity field calculated from surface drifter data (Pazan and Niiler 2004). The result of this analysis is inconclusive as the estimate of the volume flux for the surface flow was only half as big as the estimate of the error, even when using the velocities derived from the entire historical drifter dataset (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005).…”

Section: ϫ2mentioning

confidence: 99%

How Does Labrador Sea Water Enter the Deep Western Boundary Current?

Palter

Lozier

Lavender

2008

Journal of Physical Oceanography

View full text Add to dashboard Cite

Labrador Sea Water (LSW), a dense water mass formed by convection in the subpolar North Atlantic, is an important constituent of the meridional overturning circulation. Understanding how the water mass enters the deep western boundary current (DWBC), one of the primary pathways by which it exits the subpolar gyre, can shed light on the continuity between climate conditions in the formation region and their downstream signal. Using the trajectories of (profiling) autonomous Lagrangian circulation explorer [(P)ALACE] floats, operating between 1996 and 2002, three processes are evaluated for their role in the entry of Labrador Sea Water in the DWBC: 1) LSW is formed directly in the DWBC, 2) eddies flux LSW laterally from the interior Labrador Sea to the DWBC, and 3) a horizontally divergent mean flow advects LSW from the interior to the DWBC. A comparison of the heat flux associated with each of these three mechanisms suggests that all three contribute to the transformation of the boundary current as it transits the Labrador Sea. The formation of LSW directly in the DWBC and the eddy heat flux between the interior Labrador Sea and the DWBC may play leading roles in setting the interannual variability of the exported water mass.

show abstract

“…It encompasses the period since October 1992 on a 1°·1°grid with a 10-day temporal resolution. The last set of data used for of the 6-h interpolated trajectories was collected from the satellite-tracked drifting buoys by the Atlantic oceanographic and meteorological laboratory (AOML) (Pazan and Niiler 2004). These data are available on-line (http:// www.aoml.noaa.gov/phod/dac/dacdata.html) and their processing has been described by Hansen and Poulain (1996).…”

Section: Validation Datamentioning

confidence: 99%

Displacements and transformations of nitrate-rich and nitrate-poor water masses in the tropical Pacific during the 1997 El Niño

2005

View full text Add to dashboard Cite

sur l'évolution de la langue d'eau verte équatoriale enrichie en chlorophylle dans le Pacifique après le déclenchement d'un El Niño : retard à l'oligotrophie tant qu'il subsiste des nitrates dans les eaux HNLCA Lagrangian analysis was applied to the outputs of a coupled physical-biogeochemical model to describe the redistribution of nitrate-rich and nitrate-poor surface water masses in the tropical Pacific throughout the major 1997 El Niño. The same tool was used to analyze the causes of nitrate changes along trajectories and to investigate the consequences of the slow nitrate uptake in the high nutrient low chlorophyll (HNLC) region during the growth phase of the event. Three patterns were identified during the drift of water masses. The first mechanism is well known along the equator: oligotrophic waters from the western Pacific are advected eastward and retain their oligotrophic properties along their drift. The second concerns the persistent upwelling in the eastern basin. Water parcels have complex trajectories within this retention zone and remain mesotrophic. This study draws attention to the third process which is very specific to the HNLC region and to the El Niño period. During the 1997 El Niño, horizontal and vertical inputs of nitrate decreased so dramatically that nitrate uptake by phytoplankton became the only mechanism driving nitrate changes along pathways. The study shows that because of the slow nitrate uptake characteristic of the tropical Pacific HNLC system, nitrate in the pre-El Niño photic layer can support biological production for a period of several months. As a consequence, the slow nitrate uptake delays the gradual onset of oligotrophic conditions over nearly all the area usually occupied by upwelled waters. Owing to this process, mesotrophic conditions persist in the tropical Pacific during El Niño events

show abstract

New global drifter data set available

Cited by 32 publications

References 5 publications

Three decades of research on the greater Agulhas Current

Three decades of research on the greater Agulhas Current

How Does Labrador Sea Water Enter the Deep Western Boundary Current?

Displacements and transformations of nitrate-rich and nitrate-poor water masses in the tropical Pacific during the 1997 El Niño

Contact Info

Product

Resources

About