Caribbean Sea Marine Heatwaves tide to Indian Ocean Marine Heatwaves

Marine heatwaves (MHWs) are not a phenomenon confined to local areas. Instead, they may interact with other regions through specific teleconnection patterns. Numerous studies have revealed the occurrence, variability, and future trends of MHWs. However, the connections between MHWs in different regions still require further research. This study employed observational data and combined with climate model simulation results to investigate the lead-lag teleconnections of MHW between the equatorial Western Indian Ocean and the Caribbean Sea on seasonal timescales and explain the underlying mechanisms. MHWs in the equatorial Western Indian Ocean trigger atmospheric upward motion, initiating a westward-propagating Indian Ocean-Pacific-Atlantic (IPA) wave train. Influenced by the IPA, anomalous Hadley circulation and atmospheric warming occur above the Caribbean Sea, leading to intensification through increased downward latent heat flux. The IPA facilitates a close teleconnection between the MHW processes in the two ocean basins, which enables the transfer of energy and climate signals across regions, thereby further intensifying MHWs in the Caribbean Sea region.