Journal articles: 'Leeuwin Current'

1

Nürnberg, Dirk, Akintunde Kayode, Karl J. F. Meier, and Cyrus Karas. "Leeuwin Current dynamics over the last 60 kyr – relation to Australian ecosystem and Southern Ocean change." Climate of the Past 18, no. 11 (November 15, 2022): 2483–507. http://dx.doi.org/10.5194/cp-18-2483-2022.

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Abstract. The Leeuwin Current, flowing southward along the western coast of Australia, is an important conduit for the poleward heat transport and inter-ocean water exchange between the tropical and the subantarctic ocean areas. Its past development and its relationship to Southern Ocean change and Australian ecosystem response is, however, largely unknown. Here we reconstruct sea surface and thermocline temperatures and salinities from foraminiferal-based Mg/Ca and stable oxygen isotopes from areas offshore of southwestern and southeastern Australia, reflecting the Leeuwin Current dynamics over the last 60 kyr. Their variability resembles the biomass burning development in Australasia from ∼60–20 ka BP, implying that climate-modulated changes related to the Leeuwin Current most likely affected Australian vegetational and fire regimes. Particularly during ∼60–43 ka BP, the warmest thermocline temperatures point to a strongly developed Leeuwin Current during Antarctic cool periods when the Antarctic Circumpolar Current (ACC) weakened. The pronounced centennial-scale variations in Leeuwin Current strength appear to be in line with the migrations of the Southern Hemisphere frontal system and are captured by prominent changes in the Australian megafauna biomass. We argue that the concerted action of a rapidly changing Leeuwin Current, the ecosystem response in Australia, and human interference since ∼50 BP enhanced the ecological stress on the Australian megafauna until its extinction at ∼43 ka BP. While being weakest during the Last Glacial Maximum (LGM), the deglacial Leeuwin Current intensified at times of poleward migrations of the Subtropical Front (STF). During the Holocene, the thermocline off southern Australia was considerably shallower compared to the short-term glacial and deglacial periods of Leeuwin Current intensification.

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2

Rennie, Susan J., Charitha P. Pattiaratchi, and Robert D. McCauley. "Eddy formation through the interaction between the Leeuwin Current, Leeuwin Undercurrent and topography." Deep Sea Research Part II: Topical Studies in Oceanography 54, no. 8-10 (April 2007): 818–36. http://dx.doi.org/10.1016/j.dsr2.2007.02.005.

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3

Reason, CJC, and AF Pearce. "Comparison of the Semtner and Chervin eddy-resolving global ocean model with LUCIE and satellite observations in the Leeuwin Current region." Marine and Freshwater Research 47, no. 3 (1996): 509. http://dx.doi.org/10.1071/mf9960509.

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Output from the Semtner and Chervin eddy-resolving global ocean general circulation model is compared with observations from the Leeuwin Current Interdisciplinary Experiment (LUCIE) and satellite data for the coastal waters of Western Australia. The model output is a snapshot over the domain 9-43�S, 90-120�E for a day in mid July 1987, which is during the season that the Leeuwin Current is expected to be well established along the western and southern coasts of Western Australia. Maximum Leeuwin Current velocities in the model are of the order of 60 cm s-1 and are found in the southern part of the current on the western coast and around into the Great Australian Bight. At depths below about 200 m, and centred near 400 m, there is an equatorward-flowing undercurrent with maximum velocity of order 25 cm s-1. Comparison of temperature and salinity cross-sections with LUCIE observations reveals that the model output for this day exhibits many realistic features. In particular, the model fields display a number of prominent meanders and eddies on the Leeuwin Current as well as further offshore. Consistent with observations, mesoscale features associated with the Leeuwin Current are concentrated between 25�S and the Cape Mentelle region; the flow in the northern part of the Leeuwin Current and the North West Shelf may be too weak to induce eddy-generating instabilities. Prominent in the model output are two large meanders on the Leeuwin Current between 25�S and 29�S and two anticyclonic eddies further downstream; features similar to these are evident in satellite data during winter 1987.

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4

Cresswell, GR, and JL Peterson. "The Leeuwin Current south of Western Australia." Marine and Freshwater Research 44, no. 2 (1993): 285. http://dx.doi.org/10.1071/mf9930285.

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Satellite images as well as data collected in situ were used to follow the seasonal changes of the Leeuwin Current south of Western Australia (WA) in 1986-87. The current has two major sources: salty subtropical water from west of WA, and fresher tropical water from north of WA. In summer, the tropical waters are excluded by the strong equatorward wind stress. In autumn and winter, this wind stress is reduced and tropical waters flood southward to dominate the flow. Nevertheless, salty subtropical water is entrained en route, and so, whatever the season, the Leeuwin Current is more saline than the 'local' subantarctic waters off southern WA. From a research vessel, observations were made on the current and one of its offshoots in June 1987. The Leeuwin Current had a maximum surface speed of more than 1 m s-1 just beyond the shelf edge. Its warm, low-salinity surface core rode on a sheath of higher-salinity subtropical water that it had entrained upstream. The first survey of the offshoot showed it to be 50 km across and 130 m deep (for water warmer than 17�C), and it extended 200 km seaward (as deduced from a satellite image). Velocities in the offshoot ranged up to 1 m s-1 southward and 1 m s-1 north-eastward on the western and eastern sides, respectively. Richardson numbers were, in places, as low as 0.25. On a second survey two days later, the offshoot was found to have pinched off and the remnant bulge on the edge of the parent stream to have moved 30 km eastward. The flow around this bulge reached 1.6 m s-'. The offshoot/bulge was possibly first formed in April, and it kept its identity at least until August. During this time, it moved eastward at speeds between 2 and 15 km day-1. In June, the offshoot was estimated to contain water equivalent to five days' transport of the parent current.

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5

De Vleeschouwer, David, Benjamin F. Petrick, and Alfredo Martínez‐García. "Stepwise Weakening of the Pliocene Leeuwin Current." Geophysical Research Letters 46, no. 14 (July 22, 2019): 8310–19. http://dx.doi.org/10.1029/2019gl083670.

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6

Weaver, Andrew J., and Jason H. Middleton. "On the Dynamics of the Leeuwin Current." Journal of Physical Oceanography 19, no. 5 (May 1989): 626–48. http://dx.doi.org/10.1175/1520-0485(1989)019<0626:otdotl>2.0.co;2.

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7

Cresswell, G. "The Leeuwin Current near Rottnest Island, Western Australia." Marine and Freshwater Research 47, no. 3 (1996): 483. http://dx.doi.org/10.1071/mf9960483.

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Ship data and a satellite image in June 1987 showed the Leeuwin Current as a warm, low-salinity tropical stream travelling southward inshore of the 180-m isobath with near-surface speeds up to 0.9 m s-1. Farther offshore, where the waters became progressively more subtropical, the southward currents were also quite strong--0.75 m s-1 above the continental slope and over 0.4 m s-1 out to 70 km beyond the shelf edge. Beyond this, a doming of 150 m in the temperature structure at several hundred metres depth drove a cyclonic eddy that had its maximum speed of ~0.5 m s-1 in a ring at 200-400 m depth. The presence of the eddy was confirmed by the path of a drifter. Geostrophic currents and currents measured directly with an Acoustic Doppler Current Profiler showed good agreement. The warm 'shoulder' of the Leeuwin Current between the 105-m and 135-m isobaths was a biological oasis characterized by, inter alia, several fish schools at least 10 km long and 1 km wide and with vertical extents from 20 m to more than 100 m depth.

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8

Caputi, Nick, Chris Chubb, and Alan Pearce. "Environmental effects on recruitment of the western rock lobster, Panulirus cygnus." Marine and Freshwater Research 52, no. 8 (2001): 1167. http://dx.doi.org/10.1071/mf01180.

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The Leeuwin Current, which brings warm, nutrient-poor waters southward along the edge of the West Australian continental shelf, is positively correlated with western rock lobster (Panulirus cygnus) puerulus settlement along the coast. Westerly winds, also positively correlated with puerulus settlement, probably assist the transport of larvae to the coast during settlement. We examined relationships between (a) monthly sea-surface temperature where phyllosoma larvae occur – and annual levels of puerulus settlement at locations throughout the fishery and (b) monthly variation in Leeuwin Current strength (and westerly winds) and annual puerulus settlement later in the year (August–January). The Leeuwin Current, when it begins to strengthen during February–April, was highly correlated with puerulus settlement; sea-surface temperature during this period may have strongly influenced puerulus settlement at many locations. Its influence on puerulus settlement may have been due to improved larval survival and growth caused by higher water temperatures associated with a stronger Leeuwin Current in April or to increased retention of larvae close to the coast. In years when the southward-flowing Leeuwin Current was very strong, settlement in the southern locations was relatively higher than that farther north. In years of strong puerulus settlement, settlement also occurred earlier in the season.

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9

Akhir, Mohd Fadzil, Charitha Pattiaratchi, and Michael Meuleners. "Dynamics and Seasonality of the Leeuwin Current and the Surrounding Counter-Current System in the Region South of Western Australia." Journal of Marine Science and Engineering 8, no. 8 (July 23, 2020): 552. http://dx.doi.org/10.3390/jmse8080552.

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Surface circulation associated with the Leeuwin Current System off the southern coast of Western Australia was simulated using the Regional Ocean Model Systems (ROMS). The Leeuwin current (LC) and Flinders current (FC) were reproduced in two simulation: with and without wind stress. The inclusion of wind resulted in a strong LC during autumn and winter months with the LC flowing close to the shelf, accelerating after reaching the south-west corner at Cape Leeuwin. The geopotential gradient was present through all seasons, indicating that it is the major driving force of the currents. At the subsurface, continuation of the opposing undercurrent present at the southwest corner. Interchanging of strength and transport between LC and FC can be seen between seasons, where LC strength drops significantly in autumn and winter when the wind stress is low and this subsequently increases the FC transport. The FC strength declines in summer when there is no wind stress, which during this time LC is stronger. Meanwhile, the analysis shows an inshore presence of Cresswell current is evident along the coast when there is south-easterly wind in summer. The study provides comprehensive overview of the complex currents system where wind influence proves to be determining factors to the current system.

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10

Rochford, DJ. "Seasonal changes in the distribution of Leeuwin Current waters of Southern Australia." Marine and Freshwater Research 37, no. 1 (1986): 1. http://dx.doi.org/10.1071/mf9860001.

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Three major water masses occur for all or part of the year within the shelf and slope region off southern Australia. A Leeuwin Current carries the warmest water mass of relatively low salinity into the region, principally along the shelf break as far east as 130�E. This water mass first enters the western end of the region in May, disappears from the eastern end after July and from the western end by September-October. A warm and very high salinity water mass is present in the central and eastern half of the Great Australian Bight for most of the year. This central Bight water mass drifts to the south-east and occupies much of the shelf and slope region east of 135�E., particularly in winter. A West Wind Drift cold water mass of lowest salinity is found throughout the year off the slope region of southern Australia and periodically intrudes into the shelf break, especially when the Leeuwin Current is weakly developed. The central Bight waters, which provide a second source of warm waters in the eastern half of the region, greatly complicate the interpretation from satellite imagery of warm waters in that region as being derived solely from the Leeuwin Current. Adequate salinity data and sea surface temperatures derived from satellite imagery are required to determine more accurately the eastward extent of the Leeuwin Current.

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11

Nof, Doron, Thierry Pichevin, and Janet Sprintall. "“Teddies” and the Origin of the Leeuwin Current." Journal of Physical Oceanography 32, no. 9 (September 1, 2002): 2571–88. http://dx.doi.org/10.1175/1520-0485-32.9.2571.

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Abstract The outflow from the Indonesian seas empties approximately 5–7 Sv of surface warm (and low salinity) Indonesian Throughflow water into the southern Indian Ocean (at roughly 12°S). Using a nonlinear 1½-layer model with a simple geometry consisting of a point source (of anomalous water) situated along a meridional wall on a β plane, the spreading of these waters is examined. An analytical solution is constructed with the aid of the “slowly varying” approach, and process-oriented numerical simulations are performed. It is found that, immediately after emptying into the ocean, the outflow splits into two branches. One branch carries approximately 13% of the source mass flux and forms a chain of high amplitude anticyclonic eddies (lenses) immediately to the west of the source. These eddies drift westward and penetrate into the interior of the Indian Ocean. The second branch carries the remaining 87% of the mass flux via a coastal southward flowing current. Ultimately, this second branch separates from the coast and turns westward. (A detailed examination of this second branch separation is, nevertheless, beyond the scope of this study.) It is suggested that the eddies recently observed to the west of the Island of Timor are a result of the above eddy generation process, which is not related to the classical eddy generation process associated with instabilities (i.e., the breakdown of a known steady solution). It is also suggested that this new nonlinear process explains why some of the Indonesian Throughflow water forms the source of the southward flowing coastal Leeuwin Current.

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12

Thompson, R. O. R. Y. "Continental-shelf-scale model of the Leeuwin Current." Journal of Marine Research 45, no. 4 (November 1, 1987): 813–27. http://dx.doi.org/10.1357/002224087788327190.

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13

Cresswell, GR, and JL Peterson. "Corrigenda - The Leeuwin Current south of Western Australia." Marine and Freshwater Research 44, no. 2 (1993): 285. http://dx.doi.org/10.1071/mf9930285c.

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14

Morrow, Rosemary, Fangxin Fang, Michele Fieux, and Robert Molcard. "Anatomy of three warm-core Leeuwin Current eddies." Deep Sea Research Part II: Topical Studies in Oceanography 50, no. 12-13 (July 2003): 2229–43. http://dx.doi.org/10.1016/s0967-0645(03)00054-7.

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15

Smith, Robert L., Adriana Huyer, J. Stuart Godfrey, and John A. Church. "The Leeuwin Current off Western Australia, 1986–1987." Journal of Physical Oceanography 21, no. 2 (February 1991): 323–45. http://dx.doi.org/10.1175/1520-0485(1991)021<0323:tlcowa>2.0.co;2.

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16

Feng, Ming, Dirk Slawinski, Lynnath E. Beckley, and John K. Keesing. "Retention and dispersal of shelf waters influenced by interactions of ocean boundary current and coastal geography." Marine and Freshwater Research 61, no. 11 (2010): 1259. http://dx.doi.org/10.1071/mf09275.

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Retention and dispersal of shelf waters under the influence of ocean boundary currents is crucial to recruitment processes of many coastal species. In this study, a Lagrangian particle tracking method based on an eddy-resolving, data-assimilating, hydrodynamic model is used to study spatial variations of local retention rates and alongshore dispersal of surface waters on the continental shelf off the west coast of Australia. The circulation on the shelf off the west coast of Australia is dominated by the southward-flowing eastern boundary current, the Leeuwin Current, which is interrupted by episodic wind-driven, northward, inshore surface transport during the austral summer, and by mesoscale eddy formations during the austral winter. Low-retention shelf regions tend to experience high alongshore currents, owing to the near-shore influence of the Leeuwin Current, protruding coastal geography, or formation of mesoscale eddies, whereas high-retention regions are sheltered from the direct influence of the Leeuwin Current by coastal geographic features. Alongshore dispersal also exhibits spatial as well as seasonal heterogeneity, with predominantly southward dispersal during the austral winter, and more symmetrical dispersal during the austral summer. Shelf retention and seasonal dispersal are linked with recruitment processes of invertebrate and fish species off the west coast of Australia.

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17

Kolbusz, Jessica, Tim Langlois, Charitha Pattiaratchi, and Simon de Lestang. "Using an oceanographic model to investigate the mystery of the missing puerulus." Biogeosciences 19, no. 2 (January 28, 2022): 517–39. http://dx.doi.org/10.5194/bg-19-517-2022.

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Abstract. Dynamics of ocean boundary currents and associated shelf processes can influence onshore and offshore water transport, critically impacting marine organisms that release long-lived pelagic larvae into the water column. The western rock lobster, Panulirus cygnus, endemic to Western Australia, is the basis of Australia's most valuable wild-caught commercial fishery. After hatching, western rock lobster larvae (phyllosoma) spend up to 11 months in offshore waters before ocean currents and their ability to swim transports them back to the coast. The abundance of western rock lobster post-larvae (puerulus) provides a puerulus index used by fishery managers as a predictor of lobster abundance 3–4 years later. This index has historically been positively correlated with the strength of the Leeuwin Current. In 2008 and 2009, the Leeuwin Current was strong, yet a settlement failure occurred throughout the fishery, prompting management changes and a rethinking of environmental factors associated with their settlement. Thus, understanding factors that may have been responsible for the settlement failure is essential for fishery management. Oceanographic parameters likely to influence puerulus settlement were derived for 17 years to investigate correlations. Analysis indicated that puerulus settlement at adjacent monitoring sites has similar oceanographic forcing, with kinetic energy in the offshore and the strength of the Leeuwin Current being key factors. Settlement failure years were synonymous with “hiatus” conditions in the southeast Indian Ocean and periods of sustained cooler water present offshore. Post-2009, there has been an unusual but consistent increase in the Leeuwin Current during the early summer months, with a matching decrease in the Capes Current, which may explain an observed settlement timing mismatch compared to historical data. Our study has revealed that a culmination of these conditions likely led to the recruitment failure and subsequent changes in puerulus settlement patterns.

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18

Hanson, Christine E., Charitha B. Pattiaratchi, and Anya M. Waite. "Seasonal production regimes off south-western Australia: influence of the Capes and Leeuwin Currents on phytoplankton dynamics." Marine and Freshwater Research 56, no. 7 (2005): 1011. http://dx.doi.org/10.1071/mf04288.

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Temporal primary production dynamics were investigated off south-western Australia, where the summer upwelling regime of the Capes Current was compared with early winter conditions characterised by strengthened near-shore Leeuwin Current flow. Seasonal upwelling in this region sourced nitrate levels of ≥1 μm from the nutricline at the base of the Leeuwin Current’s mixed layer, with total water column production reaching a maximum of ~950 mg C m−2 day−1 in the Capes Current. Stable isotope signatures of particulate matter indicated that productivity off south-western Australia was heavily reliant on nitrate as a nitrogen source, with mean δ15N ranging from ~4 to 5 ‰ under both upwelling and non-upwelling (winter) conditions. Unexpectedly, significant nutrient enrichment within the Leeuwin Current (up to 3.1 μm nitrate) occurred during winter, likely as a result of the meandering Leeuwin Current flooding the inner shelf north of the study area and entraining relatively high-nutrient shelf waters in its southwards flow. However, early winter production under these nutrient-replete conditions (mean ± s.d. 310 ± 105 mg C m−2 day−1) was significantly lower than in summer (695 ± 140 mg C m−2 day−1) due to light limitation, both as a result of reduced surface irradiance characteristic of the winter months and significantly higher light attenuation within the water column as compared with summer conditions.

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19

Squire, Peter, Renaud Joannes-Boyau, Anja M. Scheffers, Luke D. Nothdurft, Quan Hua, Lindsay B. Collins, Sander R. Scheffers, and Jian-xin Zhao. "A Marine Reservoir Correction for the Houtman-Abrolhos Archipelago, East Indian Ocean, Western Australia." Radiocarbon 55, no. 1 (2013): 103–14. http://dx.doi.org/10.2458/azu_js_rc.v55i1.16197.

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High-precision analysis using accelerator mass spectrometry (AMS) was performed upon known-age Holocene and modern, pre-bomb coral samples to generate a marine reservoir age correction value (ΔR) for the Houtman-Abrolhos Archipelago (28.7°S, 113.8°E) off the Western Australian coast. The mean ΔR value calculated for the Abrolhos Islands, 54 ± 30 yr (1 σ) agrees well with regional ΔR values for Leeuwin Current source waters (N-NW Australia-Java) of 60 ± 38 yr. The Abrolhos Islands show little variation with ΔR values of the northwestern and north Australian coast, underlining the dominance of the more equilibrated western Pacific-derived waters of the Leeuwin Current over local upwelling. The Abrolhos Islands ΔR values have remained stable over the last 2896 cal yr BP, being also attributed to the Leeuwin Current and the El Niño Southern Oscillation (ENSO) signal during this period. Expected future trends will be a strengthening of the teleconnection of the Abrolhos Islands to the climatic patterns of the equatorial Pacific via enhanced ENSO and global warming activity strengthening the Leeuwin Current. The possible effect upon the trend of future ΔR values may be to maintain similar values and an increase in stability. However, warming trends of global climate change may cause increasing dissimilarity of ΔR values due to the effects of increasing heat stress upon lower-latitude coral communities.

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Squire, Peter, Renaud Joannes-Boyau, Anja M. Scheffers, Luke D. Nothdurft, Quan Hua, Lindsay B. Collins, Sander R. Scheffers, and Jian-xin Zhao. "A Marine Reservoir Correction for the Houtman-Abrolhos Archipelago, East Indian Ocean, Western Australia." Radiocarbon 55, no. 01 (2013): 103–14. http://dx.doi.org/10.1017/s0033822200047834.

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High-precision analysis using accelerator mass spectrometry (AMS) was performed upon known-age Holocene and modern, pre-bomb coral samples to generate a marine reservoir age correction value (ΔR) for the Houtman-Abrolhos Archipelago (28.7°S, 113.8°E) off the Western Australian coast. The mean ΔR value calculated for the Abrolhos Islands, 54 ± 30 yr (1 σ) agrees well with regional ΔR values for Leeuwin Current source waters (N-NW Australia-Java) of 60 ± 38 yr. The Abrolhos Islands show little variation with ΔR values of the northwestern and north Australian coast, underlining the dominance of the more equilibrated western Pacific-derived waters of the Leeuwin Current over local upwelling. The Abrolhos Islands ΔR values have remained stable over the last 2896 cal yr BP, being also attributed to the Leeuwin Current and the El Niño Southern Oscillation (ENSO) signal during this period. Expected future trends will be a strengthening of the teleconnection of the Abrolhos Islands to the climatic patterns of the equatorial Pacific via enhanced ENSO and global warming activity strengthening the Leeuwin Current. The possible effect upon the trend of future ΔR values may be to maintain similar values and an increase in stability. However, warming trends of global climate change may cause increasing dissimilarity of ΔR values due to the effects of increasing heat stress upon lower-latitude coral communities.

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21

Lambert, E., D. Le Bars, and W. P. M. de Ruijter. "The dynamic connection of the Indonesian Throughflow, South Indian Ocean Countercurrent and the Leeuwin Current." Ocean Science Discussions 12, no. 5 (September 25, 2015): 2231–56. http://dx.doi.org/10.5194/osd-12-2231-2015.

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Abstract. East of Madagascar, wind and surface buoyancy fluxes reinforce each other, leading to frontogenesis, outcrop and an eastward along-front flow: the South Indian Ocean Countercurrent (SICC). In the east the Leeuwin Current (LC) is a unique eastern boundary current which flows poleward along Australia. It is often described as a regional coastal current forced by an off-shore meridional density gradient or a sea surface slope, yet little is known of the forcing and dynamics that control these open ocean meridional gadients. To complete this understanding, we make use of both an ocean general circulation model and a conceptual two-layer model. The SICC impinges on west Australia and adds to a sea level slope and a southward geostrophic coastal jet: the Leeuwin Current. The SICC and the LC are thus dynamically connected. An observed transport maximum of the LC around 22° S is directly related to this impingement of the SICC. The circulation of the Indonesian Throughflow (ITF) through the Indian Ocean appears to be partly trapped in the upper layer north of the outcrop line and is redirected along this outcrop line to join the eastward flow of the SICC. Shutdown of the ITF in both models strongly decreases the Leeuwin Current transport and breaks the connection between the LC and SICC. In this case, most of the SICC was found to reconnect to the internal gyre circulation in the Indian Ocean. The Indonesian Throughflow, South Indian Ocean Countercurrent and the Leeuwin Current are thus dynamically coupled.

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22

Caputi, N., WJ Fletcher, A. Pearce, and CF Chubb. "Effect of the Leeuwin Current on the Recruitment of Fish and Invertebrates along the Western Australian Coast." Marine and Freshwater Research 47, no. 2 (1996): 147. http://dx.doi.org/10.1071/mf9960147.

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The relatively high catch of invertebrate species compared with finfish off Western Australia is in sharp contrast to other regions of the world, where finfish production usually dominates. This low level of finfish production is primarily due to the Leeuwin Current, which consists of warm, low-nutrient waters flowing south along the edge of the continental shelf of the Western Australian coast. In contrast, the other eastern boundary currents in the Southern Hemisphere (Humboldt and Benguela) are associated with upwelling of cool, nutrient-rich waters flowing north and the high rates of primary production resulting in a large finfish production. The Leeuwin Current, being the dominant oceanographic feature off Western Australia, has a major influence on the abundance of many species. The larval phase is the stage mainly affected by the current, but not always with the same result. For example, the strength of the Leeuwin Current has a significant positive influence during the larval stage of the western rock lobster (Panulirus cygnus). However, the current has a negative influence during the larval life of the scallop, Amusium balloti, in Shark Bay. Similarly for the pelagic finfish species, the current has a negative effect on larval survival of pilchards (Sardinops sagax neopilchardus) but a positive impact for whitebait (Hyperlophus vittatus). Possible mechanisms for the effect of the current include transportation of larvae and temperature effects on spawning success and on survival and growth of larvae.

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23

Shinoda, Toshiaki, Weiqing Han, Luis Zamudio, and Xue Feng. "Influence of atmospheric rivers on the Leeuwin Current system." Climate Dynamics 54, no. 9-10 (April 20, 2020): 4263–77. http://dx.doi.org/10.1007/s00382-020-05228-z.

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24

Waite, A. M., P. A. Thompson, S. Pesant, M. Feng, L. E. Beckley, C. M. Domingues, D. Gaughan, et al. "The Leeuwin Current and its eddies: An introductory overview." Deep Sea Research Part II: Topical Studies in Oceanography 54, no. 8-10 (April 2007): 789–96. http://dx.doi.org/10.1016/j.dsr2.2006.12.008.

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25

Schloesser, Fabian. "A Dynamical Model for the Leeuwin Undercurrent." Journal of Physical Oceanography 44, no. 7 (July 1, 2014): 1798–810. http://dx.doi.org/10.1175/jpo-d-13-0226.1.

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Abstract Recently, Furue et al. explored analytic solutions to a dynamical model for the Leeuwin Current system (LCS) off the coast of Western Australia. Their linear, variable density, two-layer model reduces to a one-layer system near the coast. The circulation is determined by matching solutions in the coastal and offshore regions across the “grounding line” and displays many features observed in the LCS. However, it does not include a Leeuwin Undercurrent (LUC). Here, that model is extended considering an across-shore density gradient (front) caused by relatively light, tropical water being carried poleward by the Leeuwin Current (LC). As a result of including the front, the LCS circulation changes considerably; the LC deepens and strengthens significantly toward the pole, and the LCS now includes an equatorward LUC on the offshore edge of the LC. Differences in density and sea surface height across the front both contribute to the pressure gradient driving the LUC.

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Griffin, David A., John L. Wilkin, Chris F. Chubb, Alan F. Pearce, and Nick Caputi. "Ocean currents and the larval phase of Australian western rock lobster, Panulirus cygnus." Marine and Freshwater Research 52, no. 8 (2001): 1187. http://dx.doi.org/10.1071/mf01181.

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The return of Panulirus cygnus larvae to the coast of Western Australia after nearly a year at sea and its modulation by ocean currents were addressed with an individual-based larval-transport model. The simulations implied that offshore wind-driven transport of larvae is balanced by onshore geostrophic flow. Additional simulations revealed that vertical migration behaviour was essential to larval survival through its impact on advection. The six years simulated include two of high, two of low, and two of average puerulus settlement. The most robust interannual difference of the simulations was that, when coastal sea level was low and the Leeuwin Current was weak, more early-stage larvae were lost to the north and west under the influence of the wind. Conversely, many late-stage model larvae were carried south of the fishery in years when the Leeuwin Current was strong. The fraction of model larvae remaining or arriving offshore of the fishery and metamorphosing was essentially constant from year to year, so the variation in observed puerulus settlement was not explained by the model. The results imply that the nonadvective effects of fluctuations in the Leeuwin (e.g., on temperature and primary production) were primarily responsible for the high variation in natural settlement.

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27

Griffin, David A., John L. Wilkin, Chris F. Chubb, Alan F. Pearce, and Nick Caputi. "Corrigendum to: Ocean currents and the larval phase of Australian western rock lobster, Panulirus cygnus." Marine and Freshwater Research 53, no. 3 (2002): 731. http://dx.doi.org/10.1071/mf01181_co.

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The return of Panulirus cygnus larvae to the coast of Western Australia after nearly a year at sea and its modulation by ocean currents were addressed with an individual-based larval-transport model. The simulations implied that offshore wind-driven transport of larvae is balanced by onshore geostrophic flow. Additional simulations revealed that vertical migration behaviour was essential to larval survival through its impact on advection. The six years simulated include two of high, two of low, and two of average puerulus settlement. The most robust interannual difference of the simulations was that, when coastal sea level was low and the Leeuwin Current was weak, more early-stage larvae were lost to the north and west under the influence of the wind. Conversely, many late-stage model larvae were carried south of the fishery in years when the Leeuwin Current was strong. The fraction of model larvae remaining or arriving offshore of the fishery and metamorphosing was essentially constant from year to year, so the variation in observed puerulus settlement was not explained by the model. The results imply that the nonadvective effects of fluctuations in the Leeuwin (e.g., on temperature and primary production) were primarily responsible for the high variation in natural settlement.

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Batteen, Mary L., and Ming-Jer Huang. "Effect of salinity on density in the Leeuwin Current System." Journal of Geophysical Research: Oceans 103, no. C11 (October 15, 1998): 24693–721. http://dx.doi.org/10.1029/98jc01373.

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29

PRATA, A. J., and J. B. WELLS. "A satellite sensor image of the Leeuwin current, Western Australia." International Journal of Remote Sensing 11, no. 1 (January 1990): 173–80. http://dx.doi.org/10.1080/01431169008955010.

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30

Fang, Fangxin, and Rosemary Morrow. "Evolution, movement and decay of warm-core Leeuwin Current eddies." Deep Sea Research Part II: Topical Studies in Oceanography 50, no. 12-13 (July 2003): 2245–61. http://dx.doi.org/10.1016/s0967-0645(03)00055-9.

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31

Weaver, Andrew J., and Jason H. Middleton. "An analytic model for the Leeuwin Current off western Australia." Continental Shelf Research 10, no. 2 (February 1990): 105–22. http://dx.doi.org/10.1016/0278-4343(90)90025-h.

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32

Stuart Godfrey, J., and Andrew J. Weaver. "Is the Leeuwin Current driven by Pacific heating and winds?" Progress in Oceanography 27, no. 3-4 (January 1991): 225–72. http://dx.doi.org/10.1016/0079-6611(91)90026-i.

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33

Rennie, Susan J., Robert D. McCauley, and Charitha B. Pattiaratchi. "Thermal structure above the Perth Canyon reveals Leeuwin Current, Undercurrent and weather influences and the potential for upwelling." Marine and Freshwater Research 57, no. 8 (2006): 849. http://dx.doi.org/10.1071/mf05247.

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The Perth Canyon is a focal feeding area for pygmy blue whales on the Western Australian coast. Studies aimed at elaborating oceanographic mechanisms within the canyon were conducted between 2002 and 2005. Strings of temperature loggers set around the canyon rim were used to examine the water column’s response to climatological forcing, current meanders, upwelling and downwelling. Six moorings were positioned on a plateau in 500 m of water on the northern canyon rim, and one was positioned at the canyon head. Loggers were positioned to sample the whole water column, including the Leeuwin Current and Undercurrent. Moorings revealed spatial temperature differences between the plateau and canyon head. Observed temperature features ranged temporally from seasonal to <1 day. Seasonal changes in water temperature agreed with published Leeuwin Current studies: for example, mixed layer and stratification changes were apparent. Other observed temperature changes were related to Leeuwin Current movement and wind forcing such as the summer sea breeze and winter storms. Storms induced mixing, re-stratification, downwelling and upwelling as the wind changed direction and strength. Changes lasting a day were associated with diurnal sea breezes, internal waves and possibly solitary waves. Bottom loggers indicated that upwelling and downwelling events each occurred up to 20% of the time.

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34

De Vleeschouwer, David, Marion Peral, Marta Marchegiano, Angelina Füllberg, Niklas Meinicke, Heiko Pälike, Gerald Auer, et al. "Plio-Pleistocene Perth Basin water temperatures and Leeuwin Current dynamics (Indian Ocean) derived from oxygen and clumped-isotope paleothermometry." Climate of the Past 18, no. 5 (June 1, 2022): 1231–53. http://dx.doi.org/10.5194/cp-18-1231-2022.

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Abstract. The Pliocene sedimentary record provides a window into Earth's climate dynamics under warmer-than-present boundary conditions. However, the Pliocene cannot be considered a stable warm climate that constitutes a solid baseline for middle-of-the-road future climate projections. The increasing availability of time-continuous sedimentary archives (e.g., marine sediment cores) reveals complex temporal and spatial patterns of Pliocene ocean and climate variability on astronomical timescales. The Perth Basin is particularly interesting in that respect because it remains unclear if and how the Leeuwin Current sustained the comparably wet Pliocene climate in Western Australia, as well as how it influenced Southern Hemisphere paleoclimate variability. To constrain Leeuwin Current dynamics in time and space, this project obtained eight clumped-isotope Δ47 paleotemperatures and constructed a new orbitally resolved planktonic foraminifera (Trilobatus sacculifer) stable isotope record (δ18O) for the Plio-Pleistocene (4–2 Ma) interval of International Ocean Discovery Program (IODP) Site U1459. These new data complement an existing TEX86 record from the same site and similar planktonic isotope records from the Northern Carnarvon Basin (Ocean Drilling Program (ODP) Site 763 and IODP Site U1463). The comparison of TEX86 and Δ47 paleothermometers reveals that TEX86 likely reflects sea surface temperatures (SSTs) with a seasonal warm bias (23.8–28.9 ∘C), whereas T. sacculifer Δ47 calcification temperatures probably echo mixed-layer temperatures at the studied Site U1459 (18.9–23.2 ∘C). The isotopic δ18O gradient along a 19–29∘ S latitudinal transect, between 3.9 and 2.2 Ma, displays large variability, ranging between 0.5 ‰ and 2.0 ‰. We use the latitudinal δ18O gradient as a proxy for Leeuwin Current strength, with an inverse relationship between both. The new results challenge the interpretation that suggested a tectonic event in the Indonesian Throughflow as the cause for the rapid steepening of the isotopic gradient (0.9 ‰ to 1.5 ‰) around 3.7 Ma. The tectonic interpretation appears obsolete as it is now clear that the 3.7 Ma steepening of the isotopic gradient is intermittent, with flat latitudinal gradients (∼0.5 ‰) restored in the latest Pliocene (2.9–2.6 Ma). Still, the new analysis affirms that a combination of astronomical forcing of wind patterns and eustatic sea level controlled Leeuwin Current intensity. On secular timescales, a period of relatively weak Leeuwin Current is observed between 3.7 and 3.1 Ma. Notably, this interval is marked by cooler conditions throughout the Southern Hemisphere. In conclusion, the intensity of the Leeuwin Current and the latitudinal position of the subtropical front are both long-range effects of the same forcing: heat transport through the Indonesian Throughflow (ITF) valve and its propagation through Indian Ocean poleward heat transport. The common ITF forcing explains the observed coherence of Southern Hemisphere ocean and climate records.

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35

Cresswell, GR, FM Boland, JL Peterson, and GS Wells. "Continental shelf currents near the Abrolhos Islands, Western Australia." Marine and Freshwater Research 40, no. 2 (1989): 113. http://dx.doi.org/10.1071/mf9890113.

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Recording current meters were used to identify features of the circulation of the continental shelf near the Abrolhos Islands and Rottnest Island in 1973-75. In summer, from November to March, there was a mean northward drift of 0.1 m s-1; in winter, from April to August, the mean flow was southward at 0.2 m s-1, possibly due to the spread of the Leeuwin Current onto the shelf. In all seasons, the current records had superimposed upon them a variability with period from days to weeks. The several- day period variability in the along shore currents had peaks of up to 0.5 m s-1 and was strongly correlated with sea level and with phase-lagged alongshore wind at the nearby port of Geraldton. In summer, strong southerly wind events associated with the eastward passage of highs produced sea-level troughs and northward current pulses. In winter, northwesterly storms from lows passing over Cape Leeuwin produced sea-level crests and southward current pulses. Satellite drifter tracks confirmed the summer and winter behaviour revealed by the current meter records and, further, showed that the winter behaviour extended north of the Abrolhos Islands to 26�S.

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36

Holloway, PE, and HC Nye. "Leeuwin current and wind distributions on the southern part of the Australian North West Shelf between January 1982 and July 1983." Marine and Freshwater Research 36, no. 2 (1985): 123. http://dx.doi.org/10.1071/mf9850123.

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Observations of the current and wind distributions on the southern part of the Australian North West Shelf between January 1982 and July 1983 are presented. Maps of monthly averages of winds and currents from a variety of locations are presented as well as some time series spanning 19 months of currents and water temperatures from a shelf-slope location and corresponding winds from a coastal station. The main feature of the observations is the strong flow to the south-west parallel to the bathymetry known as the Leeuwin Current. From the observations across the continental shelf, the low-frequency flow is strongest over the shelf break reaching a maximum speed of approximately 0 25 m s-1. The current is strongest between February and June. Reversals of the flow to the north- east are usually weak in strength and of short duration and are associated with strong south-west winds. However, observations of water temperature suggest the north-east currents cause weak upwelling events of cold deep water onto the shelf. The south-east trade winds blow from the south- east between March and August, but are shown to be inefficient in generating longshore currents to the south-west and hence in strengthening the Leeuwin Current.

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37

Waite, A. M., V. Rossi, M. Roughan, B. Tilbrook, P. A. Thompson, M. Feng, A. S. J. Wyatt, and E. J. Raes. "Formation and maintenance of high-nitrate, low pH layers in the eastern Indian Ocean and the role of nitrogen fixation." Biogeosciences 10, no. 8 (August 28, 2013): 5691–702. http://dx.doi.org/10.5194/bg-10-5691-2013.

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Abstract. We investigated the biogeochemistry of low dissolved oxygen high-nitrate (LDOHN) layers forming against the backdrop of several interleaving regional water masses in the eastern Indian Ocean, off northwest Australia adjacent to Ningaloo Reef. These water masses, including the forming Leeuwin Current, have been shown directly to impact the ecological function of Ningaloo Reef and other iconic coastal habitats downstream. Our results indicate that LDOHN layers are formed from multiple subduction events of the Eastern Gyral Current beneath the Leeuwin Current (LC); the LC originates from both the Indonesian Throughflow and tropical Indian Ocean. Density differences of up to 0.025 kg m−3 between the Eastern Gyral Current and the Leeuwin Current produce sharp gradients that can trap high concentrations of particles (measured as low transmission) along the density interfaces. The oxidation of the trapped particulate matter results in local depletion of dissolved oxygen and regeneration of dissolved nitrate (nitrification). We document an associated increase in total dissolved carbon dioxide, which lowers the seawater pH by 0.04 units. Based on isotopic measurements (δ15N and δ18O) of dissolved nitrate, we determine that ~ 40–100% of the nitrate found in LDOHN layers is likely to originate from nitrogen fixation, and that, regionally, the importance of N-fixation in contributing to LDOHN layers is likely to be highest at the surface and offshore.

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38

Waite, A. M., V. Rossi, M. Roughan, B. Tilbrook, J. Akl, P. A. Thompson, M. Feng, A. S. J. Wyatt, and E. J. Raes. "Formation and maintenance of high-nitrate, low pH layers in the Eastern Indian Ocean and the role of nitrogen fixation." Biogeosciences Discussions 10, no. 3 (March 1, 2013): 3951–76. http://dx.doi.org/10.5194/bgd-10-3951-2013.

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Abstract. We investigate the biogeochemistry of Low Dissolved Oxygen High Nitrate layers forming against the backdrop of several interleaving regional water masses in the Eastern Indian Ocean, off northwest Australia adjacent to Ningaloo Reef. These water masses, including the forming Leeuwin Current, have been shown directly to impact the ecological function of Ningaloo Reef and other iconic coastal habitats downstream. Our results indicate that LODHN layers are formed from multiple subduction events of the Eastern Gyral Current beneath the Leeuwin Current (LC); the LC originates from both the Indonesian Throughflow and tropical Indian Ocean. Density differences of up to 0.025 kg m−3 between the Eastern Gyral Current and the Leeuwin Current produce sharp gradients that can trap high concentrations of particles (measured as low transmission) along the density interfaces. The oxidation of the trapped particulate matter results in local depletion of dissolved oxygen and regeneration of dissolved nitrate (nitrification). We document an associated increase in total dissolved carbon dioxide, which lowers the seawater pH by 0.04 units. Based on isotopic measurements (δ15N and δ18O) of dissolved nitrate, we determine that ∼40–100% of the nitrate found in LODHN layers is likely to originate from nitrogen fixation, and that regionally, the importance of N fixation in contributing to LODHN layers is likely be highest at the surface and offshore.

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39

Paterson, Harriet, Kathy Heel, and Anya Waite. "A warm-core eddy linking shelf, Leeuwin Current and oceanic waters demonstrated by near-shelf distribution patterns of Synechococcus spp. and Prochlorococcus spp. in the eastern Indian Ocean." Marine and Freshwater Research 64, no. 11 (2013): 1011. http://dx.doi.org/10.1071/mf12271.

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In May 2006 (Austral autumn) the distribution and abundance of the cyanobacteria Synechococcus spp. and Prochlorococcus spp. were examined to assess the connectivity of a forming warm-core mesoscale eddy with the Leeuwin Current and shelf waters off south-west Western Australia. Distributions of the cyanobacteria resulted in two broad categories of samples, those dominated by Prochlorococcus spp. from subtropical and Leeuwin Current waters and those with mixed populations from shelf and eddy waters. Water temperature (21.45°C), salinity (35.46) and nitrate (0.33 μM) contributed to these groupings. Synechococcus spp. reached an integrated abundance of 3.3 × 108 cells cm–2 in warm shelf waters, with 60% of cells in G2 phase in the mid-afternoon (~16:00 hours). Cooler, nitrate-poor oceanic waters were almost exclusively inhabited by Prochlorococcus spp., with the highest abundance of 4.2 × 108 cells cm–2 in cool deep waters off the Capes in the south with 40% of cells in G2 phase in the evening (~19:00 hours). The eddy perimeter represented a clear boundary for both species, but showed connectivity between the shelf and eddy centre as both locations had a mixed community, dominated by Synechococcus spp. Eddies of the Leeuwin Current advect shelf waters, and their assemblages and productivity offshore.

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40

Batteen, Mary L., and Christopher L. Butler. "Modeling Studies of the Leeuwin Current off Western and Southern Australia." Journal of Physical Oceanography 28, no. 11 (November 1998): 2199–221. http://dx.doi.org/10.1175/1520-0485(1998)028<2199:msotlc>2.0.co;2.

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41

Griffiths, R. W., and A. F. Pearce. "Instability and eddy pairs on the Leeuwin current south of Australia." Deep Sea Research Part A. Oceanographic Research Papers 32, no. 12 (December 1985): 1511–34. http://dx.doi.org/10.1016/0198-0149(85)90101-3.

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42

Furue, Ryo, Kévin Guerreiro, Helen E. Phillips, Julian P. McCreary, and Nathaniel L. Bindoff. "On the Leeuwin Current System and Its Linkage to Zonal Flows in the South Indian Ocean as Inferred from a Gridded Hydrography." Journal of Physical Oceanography 47, no. 3 (March 2017): 583–602. http://dx.doi.org/10.1175/jpo-d-16-0170.1.

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AbstractThe Leeuwin Current System (LCS) along the coast of Western Australia consists of the poleward-flowing Leeuwin Current (LC), the equatorward-flowing Leeuwin Undercurrent (LUC), and neighboring flows in the south Indian Ocean (SIO). Using geostrophic currents obtained from a highly resolved (⅛°) hydrographic climatology [CSIRO Atlas of Regional Seas (CARS)], this study describes the spatial structure and annual variability of the LC, LUC, and SIO zonal currents, estimates their transports, and identifies linkages among them. In CARS, the LC is supplied partly by water from the tropics (an annual mean of 0.3 Sv; 1 Sv ≡ 106 m3 s−1) but mostly by shallow (200 m) eastward flows in the SIO (4.7 Sv), and it loses water by downwelling across the bottom of this layer (3.4 Sv). The downwelling is so strong that, despite the large SIO inflow, the horizontal transport of the LC does not much increase to the south (from 0.3 Sv at 22°S to 1.5 Sv at 34°S). This LC transport is significantly smaller than previously reported. The LUC is supplied by water from south of Australia (0.2 Sv), by eastward inflow from the SIO south of 28°S (1.6 Sv), and by the downwelling from the LC (1.6 Sv) and in response strengthens northward, reaching a maximum near 28°S (3.4 Sv). North of 28°S it loses water by outflow into subsurface westward flow (−3.6 Sv between 28° and 22°S) and despite an additional downwelling from the LC (1.9 Sv), it decreases to the north (1.7 Sv at 22°S). The seasonality of the LUC is described for the first time.

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43

Feng, Ming, Susan Wijffels, Stuart Godfrey, and Gary Meyers. "Do Eddies Play a Role in the Momentum Balance of the Leeuwin Current?" Journal of Physical Oceanography 35, no. 6 (June 1, 2005): 964–75. http://dx.doi.org/10.1175/jpo2730.1.

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Abstract The Leeuwin Current is a poleward-flowing eastern boundary current off the western Australian coast, and alongshore momentum balance in the current has been hypothesized to comprise a southward pressure gradient force balanced by northward wind and bottom stresses. This alongshore momentum balance is revisited using a high-resolution upper-ocean climatology to determine the alongshore pressure gradient and altimeter and mooring observations to derive an eddy-induced Reynolds stress. Results show that north of the Abrolhos Islands (situated near the shelf break between 28.2° and 29.3°S), the alongshore momentum balance is between the pressure gradient and wind stress. South of the Abrolhos Islands, the Leeuwin Current is highly unstable and strong eddy kinetic energy is observed offshore of the current axis. The alongshore momentum balance on the offshore side of the current reveals an increased alongshore pressure gradient, weakened alongshore wind stress, and a significant Reynolds stress exerted by mesoscale eddies. The eddy Reynolds stress has a −0.5 Sv (Sv ≡ 106 m3 s−1) correction to the Indonesian Throughflow transport estimate from Godfrey’s island rule. The mesoscale eddies draw energy from the mean current through mixed barotropic and baroclinic instability, and the pressure gradient work overcomes the negative wind work to supply energy for the instability process. Hence the anomalous large-scale pressure gradient in the eastern Indian Ocean drives the strongest eddy kinetic energy level among all the midlatitude eastern boundary currents.

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44

Batteen, Mary L., Richard A. Kennedy, and Henry A. Miller. "A process-oriented numerical study of currents, eddies and meanders in the Leeuwin Current System." Deep Sea Research Part II: Topical Studies in Oceanography 54, no. 8-10 (April 2007): 859–83. http://dx.doi.org/10.1016/j.dsr2.2006.09.006.

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45

Thompson, P. A., K. Wild-Allen, M. Lourey, C. Rousseaux, A. M. Waite, M. Feng, and L. E. Beckley. "Nutrients in an oligotrophic boundary current: Evidence of a new role for the Leeuwin Current." Progress in Oceanography 91, no. 4 (December 2011): 345–59. http://dx.doi.org/10.1016/j.pocean.2011.02.011.

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46

Cresswell, George R., Lars C. Lund-Hansen, and Morten Holtegaard Nielsen. "Dipole vortices in the Great Australian Bight." Marine and Freshwater Research 66, no. 2 (2015): 135. http://dx.doi.org/10.1071/mf13305.

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Shipboard measurements from late 2006 made by the Danish Galathea 3 Expedition and satellite sea surface temperature images revealed a chain of cool and warm ‘mushroom’ dipole vortices that mixed warm, salty, oxygen-poor waters on and near the continental shelf of the Great Australian Bight (GAB) with cooler, fresher, oxygen-rich waters offshore. The alternating ‘jets’ flowing into the mushrooms were directed mainly northwards and southwards and differed in temperature by only 1.5°C; however, the salinity difference was as much as 0.5, and therefore quite large. The GAB waters were slightly denser than the cooler offshore waters. The field of dipoles evolved and distorted, but appeared to drift westwards at 5km day–1 over two weeks, and one new mushroom carried GAB water southwards at 7km day–1. Other features encountered between Cape Leeuwin and Tasmania included the Leeuwin Current, the South Australian Current, the Flinders Current and the waters of Bass Strait.

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47

Cresswell, G. R., and D. A. Griffin. "The Leeuwin Current, eddies and sub-Antarctic waters off south-western Australia." Marine and Freshwater Research 55, no. 3 (2004): 267. http://dx.doi.org/10.1071/mf03115.

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Data from a research vessel cruise in late 1994 and several years of satellite observations revealed complex interactions of ocean features off south-western Australia. The ship measurements showed that the Leeuwin Current (LC) commonly ran at 0.5 m s–1 above the upper continental slope and extended down to approximately 250 m. South of the continent, a 200-km diameter anticyclonic eddy depressed the ocean structure in the upper 1000 m. The eddy showed influences of the LC, deep mixing in winter and summer heating. The sub-Antarctic water around the eddy was cooler, fresher and richer in nutrients and oxygen than both the eddy and the LC. Satellite thermal and topographic measurements showed that cyclonic eddies accelerated the LC along the southern upper continental slope, whereas anticyclonic eddies diverted it out to sea and then back again. The images suggested that weak eddies originating east of the Great Australian Bight migrate westward, first encountering the continental slope off the Recherche Archipelago. There, the anticyclonic eddies take on warm water from the LC and strengthen. Several anticyclonic eddies were followed westward beyond the archipelago for 18 months as they drifted at up to 5 km day–1 and interacted with the LC and with one another.

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48

Meuleners, Michael J., Gregory N. Ivey, and Charitha B. Pattiaratchi. "A numerical study of the eddying characteristics of the Leeuwin Current System." Deep Sea Research Part I: Oceanographic Research Papers 55, no. 3 (March 2008): 261–76. http://dx.doi.org/10.1016/j.dsr.2007.12.004.

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49

Holl, Carolyn M., Anya M. Waite, Stephane Pesant, Peter A. Thompson, and Joseph P. Montoya. "Unicellular diazotrophy as a source of nitrogen to Leeuwin Current coastal eddies." Deep Sea Research Part II: Topical Studies in Oceanography 54, no. 8-10 (April 2007): 1045–54. http://dx.doi.org/10.1016/j.dsr2.2007.02.002.

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50

Meuleners, Michael J., Charitha B. Pattiaratchi, and Gregory N. Ivey. "Numerical modelling of the mean flow characteristics of the Leeuwin Current System." Deep Sea Research Part II: Topical Studies in Oceanography 54, no. 8-10 (April 2007): 837–58. http://dx.doi.org/10.1016/j.dsr2.2007.02.003.

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Journal articles on the topic 'Leeuwin Current'

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