Oxygen isotope–salinity relationships of discrete oceanic regions from India to Antarctica vis-à-vis surface hydrological processes

Oxygen isotope distribution at shallow to intermediate depths across different fronts of the Southern Ocean: Signatures of a warm-core eddy

“…1 and Table 1 for sampling locations). Earlier studies from this region (Srivastava et al, 2007;Tiwari et al, 2013) have looked at the variability of the oxygen isotopes in the surface waters. In, the present study, the deeper depths were chosen to obtain information from surface to intermediate waters and the processes occurring therein.…”

“…Processes like evaporation/precipitation result in high slopes while those like freezing/melting that alter the salinity considerably, but not the δ 18 O values to great extent because of small isotope fractionation between seawater and ice (Beck and Münnich, 1988;Melling and Moore, 1995), result in gentle slopes (LeGrande and Schmidt, 2006;Srivastava et al, 2007;Tiwari et al, 2013). The δ 18 O value of sea ice is higher by only about 2.6-2.9‰ compared to seawater (Beck and Münnich, 1988;Melling and Moore, 1995).…”

“…We did not calculate the δ 18 O-salinity relationship for all the data together as earlier studies from the southern Indian Ocean and Southern Ocean have shown that different regions possess very distinct relationships (Srivastava et al, 2007;Tiwari et al, 2013). Therefore, we derived the δ 18 O-salinity slope for different oceanic frontal zones as shown in Fig.…”

“…One of the essential tools to study the water masses is the oxygen isotopic ratio (δ 18 O) of seawater (Bigg and Rohling, 2000;Meredith et al, 2008;Tiwari et al, 2013). It acts as a conservative tracer unless and until the water comes in contact with processes in hydrological cycle, such as evaporation, precipitation, advection, melting, and freezing (Clark and Fritz, 1997 formation in the SO using the δ 18 O values of seawater.…”

Paleoclimatic Signals from the Proxy Records of the Southern Ocean: A Review

“…Foraminifera from sediment samples faithfully record the frontal structures as revealed by the intercomparison of the plankton net and sediment samples; hence it was suggested that the past fluctuations in the extent of various fronts can be reconstructed using down-core foraminiferal isotopic content in this region (Tiwari et al, 2011). It also possible to identify discrete water masses from the SO based on the oxygen isotope and sea-surface salinity and determine the paleosalinity from carbonate fossils from the sediment based on the salinity-oxygen isotope relation (Tiwari et al, 2013).…”