The Leeuwin Current and its eddies: An introductory overview

Waite, Anya M.; Thompson, Peter A.; Pesant, Stéphane; Feng, Ming; Beckley, L.E.; Domingues, Catia M.; Gaughan, D.J.; Hanson, Christine E.; Holl, Carolyn M.; Koslow, Tony; Meuleners, Michael J.; Montoya, Joseph P.; Moore, Thomas; Muhling, Barbara A.; Paterson, H. E.; Rennie, Susan; Strzelecki, Joanna; Twomey, Luke

doi:10.1016/j.dsr2.2006.12.008

Cited by 125 publications

(111 citation statements)

References 49 publications

Supporting

Mentioning

109

Contrasting

Order By: Relevance

“…The main flow of the LC runs some 18 km offshore from the Perth metropolitan area (~12 km west of Marmion Lagoon), which increases offshore winter sea temperatures by up to 3 to 4°C . Further south, the LC tracks closer inshore before deviating eastwards along the Southern Australian coastline (Pearce 1991, Smith et al 1991, Waite et al 2007. Therefore, the LC may have had greater influence at Hamelin Bay than at Marmion Lagoon, as evidenced by relatively elevated winter sea temperatures.…”

Section: General Climatology Of Study Locationsmentioning

confidence: 99%

See 1 more Smart Citation

Satellite-derived SST data as a proxy for water temperature in nearshore benthic ecology

Smale¹,

Wernberg²

2009

Mar. Ecol. Prog. Ser.

139

133

View full text Add to dashboard Cite

Satellite-derived sea surface temperatures (SSTs) are increasingly being used as a proxy for water temperature in nearshore marine ecology, but there have been very few evaluations of how accurately SSTs reflect actual temperatures experienced by subtidal organisms. Here, we describe the benthic temperature climatology of 4 coastal locations along a ~1000 km latitudinal gradient in ocean temperature in Western Australia (WA), and compare temperature records from in situ loggers at 10 to 12 m depth with records from 2 independent satellite-derived SST datasets over 2 years. Satellite-derived SSTs were significantly correlated with in situ logger data at all locations, which demonstrate their overall ability to detect general patterns of ecological importance. However, SSTs were also significantly different from benthic water temperatures (usually 1 to 2°C higher), and they did not adequately detect ecologically important small-scale variability or provide reliable information on temperature extremes. Furthermore, rank orders of the study locations differed between the methodologies, especially in winter. We emphasize the need to carefully consider whether the accuracy and resolution of satellite-derived SSTs are appropriate for the specific ecological hypothesis being tested in nearshore subtidal habitats, and advocate the use of in situ loggers otherwise. We also highlight the suitability of the WA coastline for experimental work on the effects of temperature (and synergistic factors) on marine organisms. KEY WORDS: Benthic climatology · Satellite-derived SST · Temperature gradient · Shallow water habitats Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 387: [27][28][29][30][31][32][33][34][35][36][37] 2009 ever, this measurement is derived from the top 'skin' of seawater (~0.01 mm thick) and may not be representative of seawater temperature further down in the water column ('bulk' temperature). The relationship between 'skin' and 'bulk' temperature is strongly influenced by sea state, weather conditions and local oceanography, and has been the focus of many ground-truthing studies (Barton & Pearce 2006. It is clear that, under certain conditions, SST values may be representative of water temperatures to depths of a few meters in the open ocean (Katsaros 2003). Such observations may have prompted the use of satellite-derived SSTs in shallow-water ecological studies. However, in shallow coastal benthic habitats, factors such as tides, waves, water clarity and the thermal properties of the substratum, may influence temperature profiles and possibly reduce the correspondence between SSTs and the temperatures experienced by organisms living near the bottom. Given the severity of likely impacts, there is an increasing need to understand how organisms would respond to the current rate of global change, including ocean warming, and such an understanding is only possible if coupled with accurate environmental data. Here, we compare temperatures measured in sit...

show abstract

Section: General Climatology Of Study Locationsmentioning

confidence: 99%

“…As a result, the coastal waters off WA are warmer in winter than eastern boundary waters at comparable latitudes off South Africa and South America. Moreover, the LC suppresses wind-driven upwelling (Pearce 1991), so that surface waters remain clear and comparatively nutrient-poor (Waite et al 2007, Koslow et al 2008). …”

mentioning

confidence: 99%

Satellite-derived SST data as a proxy for water temperature in nearshore benthic ecology

Smale¹,

Wernberg²

2009

Mar. Ecol. Prog. Ser.

139

133

View full text Add to dashboard Cite

show abstract

“…The Leeuwin Current plays an important role in regional climate and ecology (Waite et al, 2007). Linear theory cannot explain such a poleward boundary current along an eastern boundary.…”

Section: Introductionmentioning

confidence: 99%

“…Linear theory cannot explain such a poleward boundary current along an eastern boundary. Early studies have pointed toward observed meridional gradients in density and steric height as a forcing agent for the LC and the influence of the ITF in reinforcing these gradients (Godfrey and Ridgway, 1985;Weaver and Middleton, 1989). Theories on the coastal trapping of the LC have focused on vertical diffusion of Rossby waves (McCreary et al, 1986) and interaction with the continental shelf (Csanady, 1978(Csanady, , 1985.…”

Section: Introductionmentioning

confidence: 99%

The connection of the Indonesian Throughflow, South Indian Ocean Countercurrent and the Leeuwin Current

2016

View full text Add to dashboard Cite

Abstract. East of Madagascar, the shallow "South Indian Ocean Counter Current (SICC)" flows from west to east across the Indian Ocean against the direction of the winddriven circulation. The SICC impinges on west Australia and enhances the sea level slope, strengthening the alongshore coastal jet: the Leeuwin Current (LC), which flows poleward along Australia. An observed transport maximum of the LC around 22 • S can likely be attributed to this impingement of the SICC. The LC is often described as a regional coastal current that is forced by an offshore meridional density gradient or sea surface slope. However, little is known about the controls of these open-ocean gradients. The regional circulation system is embedded in the subtropical "super gyre" that connects the Indo-Pacific via the Tasman Gateway and the Indonesian passages. The Indonesian Throughflow (ITF) circulates through the Indian Ocean back into the Pacific south of Australia. This return pathway appears to be partly trapped in the upper layer north of an outcrop line. It is redirected along this outcrop line and joins the eastward flow of the SICC. To study the connection of the basin-scale and the inter-oceanscale dynamics, we apply both an ocean general circulation model and a conceptual two-layer model. Shutdown of the ITF in the models leads to a large decrease in Leeuwin Current transport. Most of the SICC was found to then reconnect to the internal gyre circulation in the Indian Ocean. ITF, SICC and LC thus appear to be dynamically connected.

show abstract

“…4a) in LDOHN layers. However, we also observed lowtransparency, particle-rich layers (Karageorgis et al, 2008) at multiple locations within the mixing line between the Eastern Gyral Current waters and the more saline STW, which moves shorewards from the southwest, penetrating deeper and more regionally beneath the EGC and the forming Leeuwin Current (Waite et al, 2007b). This implies that offshore sources of particles are also likely to be important in the formation of LDOHN layers.…”

Section: Sources Of Particlesmentioning

confidence: 76%

Formation and maintenance of high-nitrate, low pH layers in the eastern Indian Ocean and the role of nitrogen fixation

et al. 2013

Self Cite

View full text Add to dashboard Cite

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

show abstract

The Leeuwin Current and its eddies: An introductory overview

Cited by 125 publications

References 49 publications

Satellite-derived SST data as a proxy for water temperature in nearshore benthic ecology

Satellite-derived SST data as a proxy for water temperature in nearshore benthic ecology

The connection of the Indonesian Throughflow, South Indian Ocean Countercurrent and the Leeuwin Current

Formation and maintenance of high-nitrate, low pH layers in the eastern Indian Ocean and the role of nitrogen fixation

Contact Info

Product

Resources

About