Given that the analysis of past monthly rainfall variability is highly relevant for the adequate management of water resources, the relationship between the climate-oceanographic indices, and the variability of monthly rainfall in Southwestern Colombia at different time scales was chosen as the research topic. It should also be noted that little-to-no research has been carried out on this topic before. For the purpose of conducting this research, we identified homogeneous rainfall regions while using Non-Linear Principal Component Analysis (NLPCA) and Self-Organizing Maps (SOM). The rainfall variability modes were obtained from the NLPCA, while their teleconnection in relation to the climate indices was obtained from Pearson’s Correlations and Wavelet Transform. The regionalization process clarified that Narino has two regions: the Andean Region (AR) and the Pacific Region (PR). The NLPCA showed two modes for the AR, and one for the PR, with an explained variance of 75% and 48%, respectively. The correlation analyses between the first nonlinear components of AR and PR regarding climate indices showed AR high significant positive correlations with Southern Oscillation Index (SOI) index and negative correlations with El Nino/Southern Oscillation (ENSO) indices. PR showed positive ones with Nino1 + 2, and Nino3, and negative correlations with Nino3.4 and Nino4, although their synchronous relationships were not statistically significant. The Wavelet Coherence analysis showed that the variability of the AR rainfall was influenced principally by the Nino3.4 index on the 3–7-year inter-annual scale, while PR rainfall were influenced by the Nino3 index on the 1.5–3-year inter-annual scale. The El Nino (EN) events lead to a decrease and increase in the monthly rainfall on AR and PR, respectively, while, in the La Nina (LN) events, the opposite occurred. These results that are not documented in previous studies are useful for the forecasting of monthly rainfall and the planning of water resources in the area of study.

中文翻译：

---

哥伦比亚西南部月降雨变率与大尺度气候指数之间的遥相关

鉴于过去月降雨量变化的分析与水资源的充分管理高度相关，因此选择气候-海洋指数与哥伦比亚西南部不同时间尺度下月降雨量变化之间的关系作为研究课题。还应该指出的是，之前几乎没有对这个主题进行过研究。为了进行这项研究，我们在使用非线性主成分分析 (NLPCA) 和自组织地图 (SOM) 的同时确定了均质降雨区域。降雨变率模式从 NLPCA 获得，而它们与气候指数的遥相关则从 Pearson 相关和小波变换获得。区域化过程阐明了 Narino 有两个区域：安第斯地区 (AR) 和太平洋地区 (PR)。NLPCA 显示了两种 AR 模式和一种 PR 模式，解释方差分别为 75% 和 48%。AR 和 PR 的第一非线性分量之间关于气候指数的相关分析表明 AR 与南方涛动指数 (SOI) 指数呈高度显着正相关，与厄尔尼诺/南方涛动 (ENSO) 指数呈负相关。PR 与 Nino1+2 和 Nino3 呈正相关，与 Nino3.4 和 Nino4 呈负相关，尽管它们的同步关系没有统计学意义。小波相干分析表明，AR降雨的变化主要受Nino3.4指数在3-7年年际尺度上的影响，而PR降雨在1年年际尺度上受Nino3指数的影响。5-3 年年际尺度。厄尔尼诺 (EN) 事件分别导致 AR 和 PR 的月降雨量减少和增加，而在拉尼娜 (LN) 事件中，则相反。这些在以前的研究中没有记录的结果对于预测月降雨量和研究区域的水资源规划很有用。