Climate variability in the southern Indian Ocean as revealed by self-organizing maps
Climate variability in the southern Indian Ocean as revealed by self-organizing maps
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DOI：
10.1007/s00382-010-0843-x
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发表时间：
2009-12
期刊：
影响因子：
4.6
通讯作者：
Y. Morioka;T. Tozuka;T. Yamagata
中科院分区：
文献类型：
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作者：
Y. Morioka;T. Tozuka;T. Yamagata
使用称为“自组织图”的非线性统计分析，研究了南印度洋海面温度（SST）的年际变化。 1951—2006年南方夏季海温异常根据正、负海温异常极点的位置不同，可分为9类。为了研究这些海温异常极的演变，利用海洋大气环流模型的输出对混合层进行热收支分析。由于正（负）海温异常极上的负（正）混合层厚度异常，气候短波辐射对混合层的增温作用增强（抑制）。短波辐射的贡献在海温异常的增长中占主导地位。与迄今为止报告的结果相比，潜热通量异常的贡献并不那么重要。分析中的差异可以通过年际混合层深度异常对气候热通量贡献的调节来解释，而在过去的研究中忽略了这一点。
Using a non-linear statistical analysis called “self-organizing maps”, the interannual sea surface temperature (SST) variations in the southern Indian Ocean are investigated. The SST anomalies during austral summer from 1951 to 2006 are classified into nine types with differences in the position of positive and negative SST anomaly poles. To investigate the evolution of these SST anomaly poles, heat budget analysis of mixed-layer using outputs from an ocean general circulation model is conducted. The warming of the mixed-layer by the climatological shortwave radiation is enhanced (suppressed) as a result of negative (positive) mixed-layer thickness anomaly over the positive (negative) SST anomaly pole. This contribution from shortwave radiation is most dominant in the growth of SST anomalies. In contrast to the results reported so far, the contribution from latent heat flux anomaly is not so important. The discrepancy in the analysis is explained by the modulation in the contribution from the climatological heat flux by the interannual mixed-layer depth anomaly that was neglected in the past studies.