Surface water temperature changes in the high latitudes of the southern hemisphere over the Last Glacial‐Interglacial Cycle
Surface water temperature changes in the high latitudes of the southern hemisphere over the Last Glacial‐Interglacial Cycle
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DOI：
10.1029/92pa00709
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发表时间：
1992-06
期刊：
影响因子：
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通讯作者：
J. Pichon;L. Labeyrie;G. Bareille;M. Labracherie;J. Duprat;J. Jouzel
中科院分区：
文献类型：
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作者：
J. Pichon;L. Labeyrie;G. Bareille;M. Labracherie;J. Duprat;J. Jouzel
利用南极硅藻化石，建立了一套估算过去海表温度的数值方程。这些方程考虑了生物地理分布和实验推导的二氧化硅溶解。这些数据是对以前使用的花卉数据库的修订和扩展，包括从渐进蛋白石溶解实验中得到的样本。对166个全新世岩心样品（124个全新世岩心顶部样品和42个人工样品）进行因子分析，确定了4个因素。其中三个因素取决于水的质量分布（一个亚南极组合和两个南极组合）；因子4对应于“溶解组合”。在数据分析中包含这一因素，可以最大限度地减少蛋白石溶解对组合的影响，并在广泛的生物硅溶解范围内准确估计海表温度。根据这些因子与夏季海温的分布，导出了一个传递函数（DTF 166/34/4）。夏季温度为−1℃~ +10℃，标准误差为±1℃。该传递函数用于估计覆盖最后一个气候周期的两个南大洋核（43°S和55°S）的海温变化。时间尺度由有孔虫氧和碳同位素比值的变化得出。重建的海温记录与南极Vostok站点的气温记录有很强的相似性，这是由冰的同位素比率变化得出的。这种相似性可用于比较海洋同位素地层学和由冰流模型得出的Vostok时间尺度。如果从表面上看，海洋时间尺度将表明在温暖期和寒冷期之间冰积累率发生了很大的变化。
A set of numerical equations is developed to estimate past sea surface temperatures (SST) from fossil Antarctic diatoms. These equations take into account both the biogeographic distribution and experimentally derived silica dissolution. The data represent a revision and expansion of a floral data base used previously and includes samples resulting from progressive opal dissolution experiments. Factor analysis of 166 samples (124 Holocene core top and 42 artificial samples) resolved four factors. Three of these factors depend on the water mass distribution (one Subantarctic and two Antarctic assemblages); factor 4 corresponds to a “dissolution assemblage”. Inclusion of this factor in the data analysis minimizes the effect of opal dissolution on the assemblages and gives accurate estimates of SST over a wide range of biosiliceous dissolution. A transfer function (DTF 166/34/4) is derived from the distribution of these factors versus summer SST. Its standard error is ± 1°C in the −1 to +10 °C summer temperature range. This transfer function is used to estimate SST changes in two southern ocean cores (43°S and 55°S) which cover the last climatic cycle. The time scale is derived from the changes in foraminiferal oxygen and carbon isotopic ratios. The reconstructed SST records present strong analogies with the air temperature record over Antarctica at the Vostok site, derived from changes in the isotopic ratio of the ice. This similarity may be used to compare the oceanic isotope stratigraphy and the Vostok time scale derived from ice flow model. The oceanic time scale, if taken at face value, would indicate that large changes in ice accumulation rates occurred between warm and cold periods.