The El Niño Southern Oscillation (ENSO) signatures interpreted in different tropical tropopause layer (TTL) parameters are investigated by using long-term Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC)-1 radio occultation temperature data from July 2006 to March 2019. The TTL parameters include the cold point tropopause height (CPT-H) and corresponding temperature (CPT-T), lapse rate tropopause height (LRT-H) and corresponding temperature (LRT-T), convective outflow level height (COH), and TTL thickness. Results indicate that the warm phase of ENSO is associated with prominent negative CPT-T anomalies, whereas the cold phase of ENSO is associated with positive CPT-T anomalies over the tropical central and eastern Pacific Ocean. Further, correlation analysis is carried out between TTL parameters obtained over the Nino 3.4 region (5°N–5°S, 170°W–120°W) and sea surface temperature Nino 3.4 Index. We found weak positive correlations in CPT-H (0.37) and LRT-H (0.49), and moderate negative correlations in CPT-T (− 0.62), LRT-T (− 0.64), and TTL thickness (− 0.5) with Nino 3.4 Index. Interestingly, a higher correlation of 0.8 is noticed between COH and the Niño 3.4 Index. Furthermore, lag correlation analysis reveals that a 4-month lag is noticed in tropopause heights (CPT-H and LRT-H) and a 2-month lag is evident in tropopause temperatures (CPT-T and LRT-T) with the Niño 3.4 Index. In addition, only 1-month lag is noticed between COH and Niño 3.4 index. With a high correlation and 1-month lag with the Nino 3.4 index, it is concluded that the COH is the most suitable TTL parameter to detect the ENSO signatures among the TTL parameters.

中文翻译：

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使用长期COSMIC RO数据在热带对流层顶层参数中观测到的ENSO签名

通过使用2006年7月至3月的气象，电离层和气候（COSMIC）-1长期星座观测系统数据，对在不同热带对流层顶层（TTL）参数中解释的厄尔尼诺南方涛动（ENSO）签名进行了研究。 2019。TTL参数包括冷点对流层顶高度（CPT-H）和对应温度（CPT-T），流逝对流层顶高度（LRT-H）和对应温度（LRT-T），对流流出水位高度（COH）和TTL厚度。结果表明，ENSO的暖期与显着的负CPT-T异常有关，而ENSO的冷期与热带中太平洋和东太平洋的CPT-T异常有关。进一步，在Nino 3.4区域（5°N-5°S，170°W-120°W）上获得的TTL参数与海面温度Nino 3.4指数之间进行了相关分析。我们发现Nino在CPT-H（0.37）和LRT-H（0.49）中呈弱正相关，在CPT-T（-0.62），LRT-T（-0.64）和TTL厚度（-0.5）中呈中等负相关。 3.4索引。有趣的是，COH与Niño3.4指数之间的相关性更高，为0.8。此外，滞后相关性分析表明，使用尼尼奥3.4时，对流层顶高度（CPT-H和LRT-H）注意到4个月的滞后，对流层顶温度（CPT-T和LRT-T）明显观察到2个月的滞后。指数。此外，COH和Niño3.4指数之间只有1个月的滞后。与Nino 3.4指数具有较高的相关性和1个月的滞后性，