Abstract Cloud base height (CBH), and equivalent potential temperature (θe) at 850 hPa are able to distinguish convective events day. The present work is analysing CBH and θe as ingredients for the formulation of a new thermodynamic index over a tropical station Kolkata during pre-monsoon season of 2016–2019. We have performed skill score analysis to evaluate the performance of new index. The result shows that the ratio CBH/θe work better than CBH or θe alone in differentiating thunderstorms. The index has been validated by taking thunderstorm cases over Kolkata from published literature, outside the index formulating period.

中文翻译：

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基于云底高度和等效位温的雷暴探测新热力学指标

摘要 云底高度 (CBH) 和 850 hPa 的等效位温 (θe) 能够区分对流事件日。目前的工作正在分析 CBH 和 θe 作为 2016 年至 2019 年季风季节前热带站加尔各答制定新热力学指数的成分。我们进行了技能评分分析来评估新指标的表现。结果表明，CBH/θe 比值在区分雷暴方面比单独使用 CBH 或 θe 效果更好。该指数已通过从已发表的文献中提取加尔各答上空的雷暴案例进行验证，超出了指数制定期。