Performance of a novel NWP–AI hybrid lightning early warning system over Indian Subcontinent
摘要
NWP models have difficulty in converting complex microphysical and dynamical processes in lightning. In contrast, data-driven AI models fail to capture the latent features associated with lightning activity. A novel NWP–AI hybrid lightning early warning system using a two-autoencoder-based classification model (C2AE), which uses IMD WRF 9 km forecast as input, is discussed. The current version of C2AE uses mean square error as a loss function and, after finetuning, can forecast lightning activity with an error of 3% when tested over the training region. Further analysis of different thunderstorm-prone regions for March–April–May 2020 reveals that C2AE can capture the spatial and temporal distribution of lightning independent of the training region.
Research highlightsA two-autoencoder-based classification model (C2AE) architecture is described. The model, when tested on the training domain, has statistically significant skills with a Bayes error of only 3%. Further analysis of model performance over different thunderstorm-prone regions for MAM 2020 shows the model is able to capture the spatial and temporal distribution of lightning activity relatively well.