Studies of El Niño and Interdecadal Variability in Tropical Sea Surface Temperatures Using a Nonnormal Filter
Studies of El Niño and Interdecadal Variability in Tropical Sea Surface Temperatures Using a Nonnormal Filter
复制标题
使用非正态滤波器研究厄尔尼诺现象和热带海面温度的年代际变化
DOI：
--
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
L. Matrosova
中科院分区：
文献类型：
--
作者：
C. Penland;L. Matrosova
摘要利用动态滤波器将热带海表温度（SST）分解为三个分量：厄尔尼诺信号、全球热带趋势和背景。这样分离出来的成分并不是独立的。相反，这一过程使我们看到了年代际信号对厄尔尼诺可预测性的重要性。以这种方式过滤的数据显示，赤道印度洋和北热带大西洋的厄尔尼诺信号非常相似。热带大西洋南部的厄尔尼诺现象导致Nino-3.4 SST异常约9个月。发现全球热带趋势的时间序列具有非常平滑的抛物线结构。在未经过滤的数据中，这种趋势与厄尔尼诺现象合谋，以掩盖一个纬向热带大西洋偶极子，这是显着的过滤背景SST数据。
Abstract A dynamically based filter is used to separate tropical sea surface temperatures (SSTs) into three components: the evolving El Nino signal, the global tropical trend, and the background. The components thus isolated are not independent. On the contrary, this procedure allows us to see the importance of the interdecadal signal to the predictability of El Nino. The data filtered in this way reveal El Nino signals in the equatorial Indian Ocean and in the north tropical Atlantic Ocean that are remarkably similar. A signature of El Nino in the south tropical Atlantic leads Nino-3.4 SST anomalies by about 9 months. The time series of a global tropical trend is found to have a very smooth parabolic structure. In unfiltered data, this trend conspires with El Nino to obscure a meridional tropical Atlantic dipole, which is significant in the filtered background SST data.