Editing Agulhas Current (section)

====Paleoclimate====
Since the [[Pleistocene]], the buoyancy of the South Atlantic [[thermocline]] and the strength of the Atlantic [[meridional overturning circulation]] has been regulated by the shedding of warm, saline Agulhas Rings.  The Agulhas leakage affects the Atlantic thermocline on a decadal timescale and over centuries it can change the buoyancy of the Atlantic thermocline and therefore the formation rates of [[North Atlantic Deep Water]] (NADW).<ref>{{Harvnb|Simon|Arthur|Hall|Peeters|2013|loc=Introduction, pp. 101-103}}</ref>

The provenance of ocean sediments can be determined by analysing [[Terrigenous sediment|terrigenous]] [[strontium]] isotope ratios in deep ocean cores.  Sediments underlying the Agulhas Current and Return Current have significantly higher ratios than surrounding sediments.  Franzese et al. 2009 analysed cores in the South Atlantic deposited during the [[Last Glacial Maximum]] (LGM, 20&nbsp;000 years ago), and concluded that the Agulhas leakage was significantly reduced.<ref>{{Cite journal|last1=Franzese|first1=A|last2=Hemming|first2=S|author-link2=Sidney Hemming|last3=Goldstein|first3=S|last4=Anderson|first4=R|date=2006-10-15|title=Reduced Agulhas Leakage during the Last Glacial Maximum inferred from an integrated provenance and flux study|journal=Earth and Planetary Science Letters|language=en|volume=250|issue=1–2|pages=72–88|doi=10.1016/j.epsl.2006.07.002|bibcode=2006E&PSL.250...72F}}</ref>  The trajectory of the current was the same during the LGM and that the reduced leakage must be explained by a weaker current.<ref>{{Cite journal|last1=Franzese|first1=Allison M.|last2=Hemming|first2=Sidney R.|author-link2=Sidney Hemming|last3=Goldstein|first3=Steven L.|date=2009|title=Use of strontium isotopes in detrital sediments to constrain the glacial position of the Agulhas Retroflection|journal=Paleoceanography|language=en|volume=24|issue=2|pages=n/a|doi=10.1029/2008PA001706|bibcode=2009PalOc..24.2217F|doi-access=free}}</ref>  Furthermore, it can be predicted that a stronger Agulhas Current will result in a more eastward retroflection and an increased Agulhas leakage.  {{Harvnb|Simon|Arthur|Hall|Peeters|2013}}, however, noted that changes in temperature and salinity in the Agulhas leakage is at least partly the result of variability in the composition in the current itself and can be a poor indicator of the strength of the leakage.<ref>{{Harvnb|Simon|Arthur|Hall|Peeters|2013|loc=Conclusions, p. 110}}</ref>