This paper presents the climatology of stratospheric intrusion into the troposphere during the Indian Summer Monsoon (ISM) observed using the mesosphere‐stratosphere‐troposphere (MST) radar located at Gadanki (13.5°N, 79.2°E). The most significant and new observation is the presence of enhanced signal‐to‐noise ratio (SNR) of 3 dB and half‐power full spectral width of >0.2 m s⁻¹ in the vicinity of tropopause during the ISM. Downdrafts (updrafts) are dominated in the vicinity of tropopause from April to June (July to March). The result of stratospheric air intrusion is also supported with 10 years of ozone measurements obtained from Aura‐Microwave Limb Sounder (MLS) and 5 years of in situ ozonesonde observations. Detailed analysis shows that the horizontal advection along with turbulence in the vicinity of tropopause caused by the tropical easterly jet and tropopause altitude variability is the prime candidate for stratosphere to troposphere transport of ozone. In contrast, the tropical tropopause temperature plays a significant role in the troposphere to stratosphere transport of water vapor during the ISM. The significance of the present study is to qualitatively constitute the climatology of these exchange processes over Gadanki using Indian MST radar.

中文翻译：

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利用MST雷达和Aura MLS测量对热带站Gadanki进行的平流层-对流层交换的长期观测

本文介绍了使用位于Gadanki（13.5°N，79.2°E）的中层-平流层-对流层（MST）雷达观测到的印度夏季风（ISM）期间平流层侵入对流层的气候学。最重要和最新的观察结果是存在增强的3 dB信噪比（SNR）和半功率全频谱宽度> 0.2 m s ^-1在ISM期间在对流层顶附近。在4月至6月（7月至3月），对流层顶附近的气流向下（上升气流）为主。平流层空气入侵的结果也得到了Aura-Microwave Limb Sounder（MLS）获得的10年臭氧测量结果和5年的原位臭氧探空仪观测结果的支持。详细的分析表明，由热带东风急流和对流层顶高度变化引起的对流层顶附近的水平对流以及湍流​​是臭氧向平流层向对流层输送的主要候选者。相反，在ISM期间，热带对流层顶温度在对流层向平流层的水蒸气输送中起着重要作用。