15- Detecting the Causal Nexus between Particulate Matter (PM10) and Rainfall in the Caribbean Area [Plocoste (2022)]

Aerosol characteristics are key parameters that define cloud properties. This article analyzes the interactions between particles (PM10) and precipitation (RR) in the framework of entropy. Our results showed that there is a bidirectional causality between PM10 concentrations and RR values. This means that PM10 concentrations influence RR values ​​while RR also acts on PM10. Rainfall seasonality has a significant impact on PM10 leaching (RR → PM10) while African dust seasonality strongly influences RR behavior (PM10 → RR). RR → PM10 is 5 times higher during the rainy season while PM10 → RR is 2.5 times more significant during the first part of the high dust season. These results revealed two types of causality: a direct causality (RR → PM10) and an indirect causality (PM10 → RR). Indeed, rainfall acts directly on PM10 concentrations while the seasonal variation of PM10 serves as an indicator of the presence of much smaller mineral particles that can act as cloud condensation nuclei.