The effects of temperature, salinity, and the carbonate system on Mg/Ca in Globigerinoides ruber (white): A global sediment trap calibration
The effects of temperature, salinity, and the carbonate system on Mg/Ca in Globigerinoides ruber (white): A global sediment trap calibration
复制标题
DOI：
10.1016/j.epsl.2017.11.026
复制
发表时间：
2018-01-15
影响因子：
5.3
通讯作者：
Fischer, Gerhard
中科院分区：
文献类型：
--
作者：
Gray, William R.;Weldeab, Syee;Fischer, Gerhard
红球盖有孔虫（白色）的Mg/Ca是一种广泛应用的热带和亚热带海表温度的代用指标。重建温度的准确性取决于Mg/Ca和温度之间的关系以及Mg/Ca的多个次级控制之间的关系的准确程度;然而，在海洋条件下，这些关系仍然很难量化。在这里，我们提出了新的校准的基础上440沉积物陷阱/浮游生物拖样品从大西洋，太平洋和印度洋，包括130个新的样品从孟加拉湾/阿拉伯海和热带大西洋。结果表明，温度、盐度和碳酸盐体系均显著影响G.块茎（白色）。我们提出了两个校正模型：第一个模型假设pH值是控制碳酸盐系统参数。在该模型中，Mg/Ca的温度敏感性为6.0 +/- 0.8%/摄氏度（2 σ），盐度敏感性为3.3 +/- 2.2%/PSU，pH敏感性为-8.3 +/- 7.7%/0.1 pH单位;第二个模型假设碳酸盐离子浓度（[CO 32-]）是控制碳酸盐系统参数。在该模型中，Mg/Ca的温度敏感性为6.7 +/- 0.8%/℃，盐度敏感性为5.0 +/- 3.0%/PSU，[CO 32-]敏感性为-0.24 +/- 0.11%/μ mol kg（-1）。在这两种型号中，温度灵敏度明显低于广泛应用的9.0 +/- 0.69%/℃的灵敏度。将我们的新校准应用于末次冰盛期的底层数据，考虑到整个海洋的盐度和碳酸盐化学变化，表明如果pH值是控制参数，热带海洋的冷却温度为2.4 +/- 1.6摄氏度，如果[CO 32-]是控制参数，则为1.5 +/- 1.4摄氏度。(C)2017爱思唯尔B. V.保留所有权利。
The Mg/Ca of planktic foraminifera Globigerinoides ruber (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 G. tuber (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 6.0 +/- 0.8%/degrees C (2 sigma), a salinity sensitivity of 3.3 +/- 2.2%/PSU and a pH sensitivity of -8.3 +/- 7.7%/0.1 pH units; The second model assumes carbonate ion concentration ([CO32-]) is the controlling carbonate system parameter. In this model, Mg/Ca has a temperature sensitivity of 6.7 +/- 0.8%/degrees C, a salinity sensitivity of 5.0 +/- 3.0%/PSU and a [CO32-] sensitivity of -0.24 +/- 0.11%/mu mol kg(-1). In both models, the temperature sensitivity is significantly lower than the widely-applied sensitivity of 9.0 +/- 0.69%/degrees C. Application of our new calibrations to down-core data from the Last Glacial Maximum, considering whole ocean changes in salinity and carbonate chemistry, indicate a cooling of 2.4 +/- 1.6 degrees C in the tropical oceans if pH is the controlling parameter and 1.5 +/- 1.4 degrees C if [CO32-] is the controlling parameter. (C) 2017 Elsevier B.V. All rights reserved.