agulhas return current

The marine atmospheric boundary layer (MABL) response to sea surface temperature (SST) perturbations with wavelengths shorter than 30° longitude by 10° latitude along the Agulhas Return Current (ARC) is described from the first year of SST and cloud liquid water (CLW) measurements from the Advanced Microwave Scanning Radiometer (AMSR) on the . The Agulhas Current system transports heat and salt from the Indian Ocean into the South Atlantic Ocean via the Agulhas leakage, which influences the . The remaining water is transported into the South Atlantic Gyre in the Agulhas Leakage. The system is fed, primarily, by the recirculation of a Southwest Indian Being a warm western boundary current in the Southern Indian Ocean subtropical gyre, the Agulhas Current is primarily driven by the large-scale wind stress curl between the Southern Hemisphere westerlies and southeast trade winds (Lutjeharms, 2006 ). The Agulhas Current is a strong western boundary current in the Indian Ocean, which flows southwards along the coast of Africa before turning back into the Indian Ocean as the Agulhas Return Current (Lutjeharms, 2006). Occasionally there is separation between the two and a definite Agulhas Front can be observed along with the Subtropical Convergence proper. The impact of SST biases in the tropical east pacific and ... Warren, 1993]. The Agulhas Return Current (ARC) is one of the current systems in the Southern Indian Ocean (SIO) associated with high Chlorophyll-a Concentrations (CC). Agulhas Return Current | Ocean Climate Stations The Agulhas Return Current constitutes the intense flow along the Subtropical Convergence south of Africa. During this retroflection process, relatively warm and saline water from the Indian Ocean leaks into the South Atlantic by the . In the Monsoon zone, the ocean's surface circulates in reverses at least twice a year, featuring the two large opposing gyres, which develop in the Arabian Sea and the Bay of Bengal. The currents of the two oceans meet at the point where the warm-water Agulhas current meets the cold-water Benguela current and turns back on itself. On Radar Signatures of Upwelling. Related images: 600 x 277 32 KB - JPEG. Interannual Eddy Kinetic Energy Modulations in the Agulhas ... the greater Agulhas Current, INDIA has a horizontal resolu-tion ranging from 30 to 40km. JPEG. PDF Journal of Geophysical Research: Oceans the Agulhas Return Current. Comparisons are made with a similar hydrographic section at the Greenwich Meridian and several notable differences are found. All subsurface instruments on the wire continued to function while the buoy drifted eastward. 2. Methods used by Warren and later modified by Niiller and Robinson have been used to investigate the Agulhas Current and other currents associated with it. The Agulhas Return Current forms part of the final outflow of the system and current knowledge on that current is appraised. The Agulhas Return Current flows eastward and exhibits a quasi-stationary meandering pattern of wavelength 500 km between 38° and 40° S. Its core width is about 70 km with an associated transport of 44±5 Sv in the upper 1000 m (Boebel et al., 2003). Because of the problems of mixed water masses, the La-grangian volume transport might be a more appropriate mea-sure of the magnitude of Agulhas leakage in a numerical model. The Agulhas Return Current emerges as a strong current as far east as 40°E which forms a marked front that is separate from the Subtropical Front, and can be distinguished by a separate water mass. About author: Werner ALPERS (1936 . The surface of the modern-day southern Agulhas Current experiences annual temperature variations averaging around 21 °C during winter months and 26 °C during summer months with a mean annual . Watch Circle: 3.5km Radius. What is at the bottom of Africa? 1200 x 1200 The Agulhas Return Current (ARC) is one of the current systems in the Southern Indian Ocean (SIO) associated with high Chlorophyll-a Concentrations (CC). In this study, we investigate the role that the solubility and biological pumps have on CO₂ variability across the Agulhas Current system ( Agulhas Current and the Agulhas Return Current). The Agulhas Return Current (ARC) separates warm subtropical water to the north from cold subpolar water to the south and marks the location of vigorous air-sea interaction processes (e.g., Jury and Walker 1988; Jury 1994; Rouault and Lutjeharms 2000; O'Neill et al. The open-ocean strong currents, sharp fronts, an d energetic synoptic variability make WBCEs challenging regio ns to observe, but existing te chnology will allow Once it extends beyond the tip of Africa, it retroflects toward the east feeding the Agulhas Return Current (ARC) that flows as a quasi-stationary . Al-though equatorward migration of the STF and reduction in Agulhas leakage were reported during the last glacial pe-riod, the fate of ARC during the last glacial-interglacial cy-cle is not clear. This method is a well-established methodology for ocean models ( Durgadoo et al. The Agulhas Return Current (ARC) Ocean Climate Station mooring preparing to be deployed on the South African Fisheries Research Ship Algoa at 38.5 o S, 30 o E, on the edge of the warm ARC southeast of South Africa (Picture: NOAA) It forms the connecting link between the generically similar South Atlantic Current and the South Indian Ocean Current, thus contributing to the water exchange between these two basins. 1300 x 600 1 MB - PNG. This work presents the seasonal and inter . In the following section, the AMSR SST and CLW data, QuikSCAT wind data, and Reynolds SST analyses are described in detail. Agulhas current system (ACS) The ACS, located along the east coast of Southern Africa, consists of the Agulhas Current, the Agulhas retroﬂection, Agulhas rings that are spawned at the retroﬂection and ﬂow westward, and the eastward ARC [Figure 1(a)]. Institute of Oceanography, University of Hamburg, Hamburg 20146, Germany. Introduction This is done for every single year of each model experiment, leading to annual time series of the AC, the Agulhas Return Current and Agulhas leakage transport. The comparison with a Lagrangian method to mea- Indian Ocean basin most of the slope current is entrained in the deep return ﬂow of the Agulhas Current or ARC, leaving only 2-3 Sv to continue north. It is estimated that up to 85 Sv (Sv) of the net transport is returned to the Indian Ocean through the retroflection. Agulhas Return Current Reference Station Vetting Page The ARC mooringwas deployed 30 November 2010 at 30E, 38.5S and broke away from its anchor on 16 January 2011. 1.1.2 Pathway 1- Agulhas Return Current . joins with the Agulhas Return Current before reaching what is considered to be the proper retroﬂection region. 2009 analysed cores in the South Atlantic deposited during the Last Glacial Maximum (LGM, 20 000 years ago), and concluded that the Agulhas leakage was significantly reduced. 164 x 76 JPEG. Reason for Mission Aquarius: Variations in salinity influence the ocean's deep circulation, outline the path freshwater ta. Igor Kamenkovich, ikamenkovich@miami.edu. Yeager, 2009]. The dynamics of the retroﬂection are an interplay between the wind forcing, inertia, bathymetry and non-linear dynamics (see box 1 in Beal et al.,2011). The objective of this work is to investigate meridional migration and eddy kinetic energy (EKE) trends in the ARC over the past 27 years using satellite-derived altimetry products. The two main currents in the ocean are the Agulhas Return Current and Agulhas Current, controlled by the monsoon. The Agulhas Return Current (ARC) in the South Indian Ocean is one of the most powerful, but one of the least studied oceanic currents. It can reach velocities of up to 4 knots (7.4 km/h; 4.6 mph) and is therefore popular among participants in trans-oceanic sailing races. To demonstrate the use of the LACCE, the Agulhas Current position outputs from the algorithm computed over a 26-year period (1993 to 2018) are then used to describe the spatial and temporal variability of the Retroflection. Agulhas Return Current South Atlantic Current 200E 400E IOOW IOOE . It flows down the east coast of Africa from 27°S to 40°S (Gordon, 1985). The resulting geographical The algorithm is applied to a state-of-the-art ocean model. As it passes the southern tip of Africa, the Current turns eastward, back towards the Indian Ocean. Blooms in the Agulhas Return Current. A new location needs to be found that will be easier for the mooring to survive. The Agulhas Return Current (ARC) meanders east from the southern tip of Africa The Agulhas Return Current ( ARC) is an ocean current in the South Indian Ocean. This project will use numerical models and observational data to explore the variability and dynamics of the ARC and its heat transport. The Agulhas Current is the western boundary current of the South Indian Ocean's subtropical gyre. Related images: 600 x 600 77 KB - JPEG. This is described and discussed, based on what information has been gained from research over the past . Sediments underlying the Agulhas Current and Return Current have significantly higher ratios than surrounding sediments. At the retroﬂection itself, mesoscale ed- The analysis region is 27° to 60°S, 0° to 100°E, encompassing the Agulhas Retroflection and the Agulhas Return Current south of Africa. The Agulhas Current forms an important link in the global ocean thermohaline circulation by its role in the inter‐ocean exchange of water south of Africa. This water becomes the Agulhas Return Current, rejoining the Indian Ocean Gyre. The Agulhas Current transports surface and intermediate waters from the tropical Indian Ocean southward along the east coast of Africa. The Agulhas Return Current maintains its retroflected position despite the fact that it is not forced to do so after its initial formation. The Agulhas Return Current (ARC) meanders east from the southern tip of Africa The Agulhas Return Current(ARC) is an ocean currentin the South Indian Ocean. The AR-001 mooring line separated in a splice in the 3/4" nylon, 1415 m below the surface buoy on January 11, 2011. Air‐sea interaction processes that modify the sea surface temperature (SST) front in the Agulhas Return Current region (between 40°E and 55°E) during austral summer and winter are examined using observational data and output from a high‐resolution ocean general circulation model. The source water at its northern end is derived from Mozambique channel eddies (de Ruijter et al., 2002) and the East Madagascar . The Agulhas Return Current tends to follow the Subtropical Convergence, which is a weak front in the South Atlantic. [1] Millennial-scale Agulhas Current variability and its implications for salt-leakage through the Indian-Atlantic Ocean Gateway Margit H. Simon, Kristina L. Arthur, Ian R. Hall, Frank J.C. Peeters, Benjamin R. Loveday, Stephen Barker, Martin Ziegler, Rainer Zahn the Agulhas Return Current from the southern limb of the subtropical "supergyre" south of Africa. It carries tropical and subtropical waters poleward, along the east coast of South Africa, between about 27 S and 37 S. South of the continent, at about 40 S, it retroflects to the east and becomes the Agulhas Return Current. Furthermore, Blanke et al. 40's 50 350 E The Agulhas Return Current forms part of the final outflow of the system and current knowledge on that current is ap-praised. The Agulhas Return Current constitutes the intense flow along the Subtropical Convergence south of Africa. Office of Naval Research . Employing the trajectories of Lagrangian ﬂoats is The nested regional model set up to simulate ocean dynamics and mesoscale variability of the greater Agulhas Current system covers the region from the Mozambique Channel to the Agulhas retroflection and the Agulhas Return Current. The Agulhas Return Current (ARC) Ocean Climate Station mooring preparing to be deployed on the South African Fisheries Research Ship Algoa at 38.5 o S, 30 o E, on the edge of the warm ARC southeast of South Africa (Picture: NOAA) Ocean Remote Sensing Institute, Ocean University of China, Qingdao 266003, China. In this case, there is no leakage, owing to 'inertial choking'. By disentangling the large-scale forcing which affects the small-scale statistics, we found . Scope: 1.15. This exchange couples the wind- However, the nature and variability of the Agulhas Return Current (ARC) is still relatively unknown, leading to uncertainty in its response to gyre intensification. The budget analyses are performed over the upper 50-m layer within which the ocean is Published January 3, 2000. The eastward path of the ARC is not a straightforward trajectory, but instead consists of a series of meanders (Boebel et al., 2003). In JanFeb 2012, the Naval Research Laboratory and collaborators carried out a field experiment in which seismic and traditional hydrographic observations were acquired to examine frontal zone mixing . These perturbations may furthermore force the current to intersect shallow regions resulting in . It flows along the continental slope, separates from the Agulhas Bank south of Africa,. These fluctuations are a result of the retroflection process, which influences the upstream conditions through the radiation of Kelvin waves along . The sources of the Agulhas Current are the East Madagascar Current (25 Sv), the Mozambique Current (5 Sv) and a recirculated part of the south-west Indian subgyre south of Madagascar, and flows down the east coast of Africa from 27°S to 40°S. 39. Detailed mechanisms for frontogenesis/frontolysis of the Agulhas Return Current (ARC) Front, defined as the maximum of the meridional sea surface temperature (SST . It forms the connecting link between the generically similar South Atlantic Current and the South Indian Ocean Current, thus contributing to the water exchange between these two basins. (O'Neill, L. W., D. B. Chelton, S. K. Esbensen and F. J. Wentz) Global high-resolution satellite observations of sea-surface temperature for numerical weather prediction and . The ARC contributes to the water exchange between oceans by forming a link between the South Atlantic Current and the South Indian Ocean Current. Climate, 2005, 18, 2706-2723. the Agulhas Return Current to highlight the oceanic processes com-pensating the strong ocean heat release (Fig. The strong air-sea interaction is intimately linked to the Southern Annular. J. Texas Dust Storm. Agulhas Return Current (ARC) [Lutjeharms and Ansorge, 2001], which ﬂows eastward. Conversely, for large inertia, or with the latitude of zero wind stress curlmuch closer to the continent, the full Agulhas Current would loop back into the Indian Ocean. This meandering path of the ARC has maintained the Hence, rectification of the double-ITCZ bias and a better representation of the Agulhas Current . The Agulhas Return Current (ARC) is an ocean current in the South Indian Ocean.The ARC contributes to the water exchange between oceans by forming a link between the South Atlantic Current and the South Indian Ocean Current. Thus, the Agulhas becomes the Agulhas Return Current, rejoining the Indian Ocean Gyre, which . This process of ring shedding at the current's retroflection is dependent on perturbations to its trajectory that are sensitive to bathymetry. The sources of the Agulhas Current have been a con-troversial subject for many years and this dispute continues. This work presents the seasonal and inter . This is described and discussed, based on what information has been gained from research over the past three . focusing on Agulhas Current, Agulhas Return Current and an eddy over the Agulhas Plateau; thus the second pathway will not be included in this study. Author: Administrator Created Date: 3/21/2016 2:49:43 PM . , 2013 ; Biastoch et al. Mooring Type: Slack-Line. Leakage responds proportionally to the intensity of westerlies up to a certain point. inertia the full Agulhas Current would turn west into the Atlantic and feed the Southern Hemisphere supergyre 8. Astrid van Veldhoven investigated the Agulhas eddies. 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