摘要 : <![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" view="all" class="author"><ce:section-title id="st0010">Abstract</ce:section-title><ce:abstract-sec id=... 展开 <![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" view="all" class="author"><ce:section-title id="st0010">Abstract</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0110" view="all">The Mg/Ca of planktic foraminifera<ce:italic>Globigerinoides ruber</ce:italic>(white) is a widely applied proxy for tropical and sub-tropical sea-surface temperature. The accuracy with which temperature can be reconstructed depends on how accurately relationships between Mg/Ca and temperature and the multiple secondary controls on Mg/Ca are known; however, these relationships remain poorly quantified under oceanic conditions. Here, we present new calibrations based on 440 sediment trap/plankton tow samples from the Atlantic, Pacific and Indian Oceans, including 130 new samples from the Bay of Bengal/Arabian Sea and the tropical Atlantic Ocean. Our results indicate temperature, salinity and the carbonate system all significantly influence Mg/Ca in<ce:italic>G. ruber</ce:italic>(white). We propose two calibration models: The first model assumes pH is the controlling carbonate system parameter. In this model, Mg/Ca has a temperature sensitivity of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" display="inline" overflow="scroll"><mml:mn>6.0</mml:mn><mml:mo>±</mml:mo><mml:mn>0.8</mml:mn><mml:mtext>%</mml:mtext></mml:math>/°C (2<ce:italic>σ</ce:italic>), a salinity sensitivity of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.gif" display="inline" overflow="scroll"><mml:mn>3.3</mml:mn><mml:mo>±</mml:mo><mml:mn>2.2</mml:mn><mml:mtext>%</mml:mtext></mml:math>/PSU and a pH sensitivity of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si3.gif" display="inline" overflow="scroll"><mml:mo>?</mml:mo><mml:mn>8.3</mml:mn><mml:mo>±</mml:mo><mml:mn>7.7</mml:mn><mml:mtext>%</mml:mtext></mml:math>/0.1 pH units; The second model assume 收起