Divergence between Antarctic and South American marine invertebrates: What molecular biology tells us about Scotia Arc geodynamics and the intensification of the Antarctic Circumpolar Current

AbstractThe Chilean species traditionally assigned to the genera Chlamys Röding, 1798 or Zygochlamys Ihering, 1907 are now placed in two new endemic South American taxa: Dietotenhosen n. gen. (middle Miocene–early middle Pliocene), to include the southeastern Pacific Ocean species D. hupeanus (Philippi, 1887) n. comb. and D. remondi (Philippi, 1887) n. comb., and Ckaraosippur n. gen. (earliest middle Miocene–Pliocene), for C. calderensis (Möricke, 1896) n. comb. (Chile) and C. camachoi n. sp. (Argentina). Both genera are the youngest survivors of the tribe Chlamydini in southern South America. None of them is related to the circumpolar genus Psychrochlamys Jonkers, 2003, and the previous proposal of the dispersal through the Antarctic Circumpolar Current for the species included herein in Dietotenhosen is rejected.UUID: http://zoobank.org/61b4bb50-321f-4b78-9069-609178ef0817

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Drake Passage and the Scotia arc: A tortuous space-time gateway for the Antarctic Circumpolar Current

Geology ◽

10.1130/focus042014.1 ◽

2014 ◽

Vol 42 (4) ◽

pp. 367-368 ◽

Cited By ~ 7

Author(s):

I. W. D. Dalziel

Keyword(s):

Antarctic Circumpolar Current ◽

Drake Passage ◽

Space Time ◽

Scotia Arc ◽

Circumpolar Current ◽

The Antarctic

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A linear model of the Antarctic circumpolar current

Journal of Fluid Mechanics ◽

10.1017/s0022112068000868 ◽

1968 ◽

Vol 32 (3) ◽

pp. 465-488 ◽

Cited By ~ 48

Author(s):

A. E. Gill

Keyword(s):

Antarctic Circumpolar Current ◽

Drake Passage ◽

Friction Model ◽

South American ◽

Average Width ◽

Friction Parameter ◽

Circumpolar Current ◽

Zonal Models ◽

The Antarctic ◽

Numerical And Analytical Methods

A simple frictional wind-driven model of the Antarctic circumpolar current is examined. The geometry includes what are thought to be the main features effecting the current, namely a gap corresponding to Drake Passage and a partial barrier corresponding to the South American peninsula. Solutions obtained by both numerical and analytical methods are presented. The analytic solution, valid for small values of a friction parameter, enables the total rate of transport of water by the current to be calculated as a function of the friction parameter and the wind stress distribution. The width which controls the rate of transport by the current tends to be the narrowest encountered rather than the average width as assumed in earlier zonal models. However, the current spreads out to several times this width due to frictional effects. The values of the eddy viscosity required to give a rate of transport of the observed order are about 103cm2/s for a bottom-friction model and of the order of 108cm2/s for a lateral friction model.

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Nonlinear Differential Equations Modeling the Antarctic Circumpolar Current

Journal of Mathematical Fluid Mechanics ◽

10.1007/s00021-021-00618-7 ◽

2021 ◽

Vol 23 (4) ◽

Author(s):

Jifeng Chu ◽

Kateryna Marynets

Keyword(s):

Fixed Point ◽

Differential Equations ◽

Boundary Conditions ◽

Topological Degree ◽

Antarctic Circumpolar Current ◽

Fixed Point Theorems ◽

Nonlinear Differential Equations ◽

Existence Results ◽

Circumpolar Current ◽

The Antarctic

AbstractThe aim of this paper is to study one class of nonlinear differential equations, which model the Antarctic circumpolar current. We prove the existence results for such equations related to the geophysical relevant boundary conditions. First, based on the weighted eigenvalues and the theory of topological degree, we study the semilinear case. Secondly, the existence results for the sublinear and superlinear cases are proved by fixed point theorems.

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