ANALYSIS OF MITOCHONDRIAL DNA DIVERSITY WITHIN AND BETWEEN NORTH AND SOUTH ATLANTIC RIGHT WHALES

North and South Atlantic lateral volume exchange is a key component of the Atlantic Meridional Overturning Circulation (AMOC) embedded in Earth’s climate. Northward AMOC heat transport within this exchange mitigates the large heat loss to the atmosphere in the northern North Atlantic. Because of inadequate climate data, observational basin-scale studies of net interbasin exchange between the North and South Atlantic have been limited. Here ten independent climate datasets, five satellite-derived and five analyses, are synthesized to show that North and South Atlantic climatological net lateral volume exchange is partitioned into two seasonal regimes. From late-May to late-November, net lateral volume flux is from the North to the South Atlantic; whereas from late-November to late-May, net lateral volume flux is from the South to the North Atlantic. This climatological characterization offers a framework for assessing seasonal variations in these basins and provides a constraint for climate models that simulate AMOC dynamics.

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Evolutionary history of birds across southern Australia: structure, history and taxonomic implications of mitochondrial DNA diversity in an ecologically diverse suite of species

Emu - Austral Ornithology ◽

10.1071/mu14047 ◽

2015 ◽

Vol 115 (1) ◽

pp. 35-48 ◽

Cited By ~ 32

Author(s):

Gaynor Dolman ◽

Leo Joseph

Keyword(s):

Mitochondrial Dna ◽

Evolutionary History ◽

Dna Diversity ◽

History Of ◽

Taxonomic Implications

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The Role of Oceanic Heat Advection in the Evolution of Tropical North and South Atlantic SST Anomalies*

Journal of Climate ◽

10.1175/jcli3961.1 ◽

2006 ◽

Vol 19 (23) ◽

pp. 6122-6138 ◽

Cited By ~ 30

Author(s):

Gregory R. Foltz ◽

Michael J. McPhaden

Keyword(s):

Surface Flux ◽

South Atlantic ◽

Shortwave Radiation ◽

Heat Advection ◽

Horizontal Advection ◽

Latent Heat Loss ◽

North And South ◽

Sst Gradient ◽

Sst Anomalies

Abstract The role of horizontal oceanic heat advection in the generation of tropical North and South Atlantic sea surface temperature (SST) anomalies is investigated through an analysis of the oceanic mixed layer heat balance. It is found that SST anomalies poleward of 10° are driven primarily by a combination of wind-induced latent heat loss and shortwave radiation. Away from the eastern boundary, horizontal advection damps surface flux–forced SST anomalies due to a combination of mean meridional Ekman currents acting on anomalous meridional SST gradients, and anomalous meridional currents acting on the mean meridional SST gradient. Horizontal advection is likely to have the most significant effect on the interhemispheric SST gradient mode through its impact in the 10°–20° latitude bands of each hemisphere, where the variability in advection is strongest and its negative correlation with the surface heat flux is highest. In addition to the damping effect of horizontal advection in these latitude bands, evidence for coupled wind–SST feedbacks is found, with anomalous equatorward (poleward) SST gradients contributing to enhanced (reduced) westward surface winds and an equatorward propagation of SST anomalies.

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