Large-Scale Atlantic Salinity Changes over the Last Half-Century: A Model–Observation Comparison
Large-Scale Atlantic Salinity Changes over the Last Half-Century: A Model–Observation Comparison
复制标题
过去半个世纪的大规模大西洋盐度变化：模型与观测的比较
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
B. Ingleby
中科院分区：
文献类型：
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作者：
A. Pardaens;M. Vellinga;P. Wu;B. Ingleby
世纪后半叶，北方大西洋的大规模淡水化和低纬度大西洋上层的盐度增加已被广泛报道。人为和/或非强迫变率过程在这些变化中的作用，以及高纬度增淡减缓大西洋纬向翻转环流（MOC）的潜力，一直是争论的主题。这些问题进行了调查，通过比较观测和模拟的变化，使用第三哈德利中心耦合模型（HadCM 3）。这一分析表明，所观察到的趋势的很大一部分可能与MOC的多年变化。使用SST衍生的历史MOC变化代理，结合模型内部变异关系，表明观察到的北方大西洋淡水含量的大部分演变可以解释为由非受迫MOC变异驱动。HadCM 3模拟与“外部”的历史时变力.
Abstract Large-scale freshening of the northern Atlantic, and concurrent salinity increases in the low-latitude Atlantic upper layers, have been widely reported for the second half of the twentieth century. The role of anthropogenic and/or unforced variability processes in these changes, and the potential for the high-latitude freshening to slow the Atlantic meridional overturning circulation (MOC), have been the subject of debate. These issues are investigated by comparing observed and simulated changes, using the Third Hadley Centre Coupled Model (HadCM3). This analysis suggests that a substantial part of the observed trends could be related to multidecadal variability of the MOC. Using an SST-derived proxy for historical MOC changes, in conjunction with model internal variability relationships, suggests that much of the observed evolution of northern Atlantic freshwater content can be explained as being driven by unforced MOC variability. HadCM3 simulations with “external” historical time-varying forci...