Analysis of the nonlinear behaviour of rainfall over Kerala

In the current era of climate change, variability in rainfall patterns is an important research topic. This is significant in the context of extreme weather events and disasters, as well as in the context of the availability of usable water for communities. The current study presents an investigation into the nonlinear characteristics of rainfall over Kerala, India. The majority of rainfall received over Kerala is during the summer monsoon season (from June to September). However, a good amount of rainfall is obtained during the winter monsoon which is from October to December, as well as during the pre-monsoon season. Here the technique of correlation dimension is utilized to study nonlinear systems exhibiting intricate interdependencies over time. By calculating a value known as correlation dimension, if it is increasing with a parameter called embedding dimension, it would reveal the occurrence of complexity and unpredictability in the rainfall patterns. Otherwise, if correlation dimension stabilizes beyond a certain point, it would suggest that the rainfall dynamics settle into a more stable and potentially predictable pattern. The findings of this analysis revealed that if the embedding dimension increases, the correlation dimension also increases, indicating the existence of complexity and unpredictability in the rainfall pattern.