Paleosalinity

From Bjerrum plots, it is found that a decrease in the salinity of an aqueous fluid will act to increase the value of the carbon dioxide-carbonate system equilibrium constants, (pK*).Of crucial importance for paleoclimatology is the observation that an increase in salinity will thus reduce the solubility of carbon dioxide in the oceans.[2] Adkins et al. (2002) used pore fluid chlorinity in ODP cores, with the paleo-depth estimated from nearby coral horizons.Adkins' study found that global salinity increased with a global sea level drop of 120 m. Analyzing 18O data they also found that deep waters were within error of the freezing point, with oceanic waters exhibiting a greater degree of homogeneity in temperatures.Today the NADW is more salty because of the Gulf Stream; this could thus indicate a reduction of flow through the Florida Straits due to lowered sea level.The extreme value of 37.1 psu is assumed to be a consequence of an increased degree of sea ice formation and export.
ocean basinBjerrum plotscarbonatecarbon dioxideseawaterpaleoclimatologysalinitysolubilitysea levellast glacial maximumice sheetsoutgassingmeridional overturning circulationthermohaline circulationisopycnalschlorinityNorth Atlantic Deep WaterAntarctic Bottom WaterGulf StreamFlorida StraitsSouthern Oceansea iceisotopic fractionationthermal expansion coefficienthaline contraction coefficientFresh waterBibcode