Climatic Trends of Ocean and Atmospheric Parameters Over South China Sea and Southeast Asia Region

Abstract The South China Sea (SCS) and Southeast Asia (SEA) are geographically significant regions with global importance due to their strategic trading routes and rapidly developing economies. Understanding how ocean–atmosphere parameters evolve in these areas is critical, particularly as climate change intensifies risks to both human and environmental systems. This study investigates long-term climatic trends in five key parameters; Sea Surface Temperature (SST), Ocean Heat Content (OHC), Sea Level Anomaly (SLA), land surface temperature, and rainfall, using datasets spanning at least 30 years. Results reveal pronounced warming signals, with SST and OHC showing consistent upward trends aligned with global observations, while SLA demonstrates moderate increases driven by thermal expansion and regional monsoon changes. Over SEA, land surface temperatures show a moderate rise, while rainfall exhibits stronger seasonal variability and increasing trend. Short-term anomalies, especially during the strong 2015 El Niño and prolonged 2022 La Niña, highlight the influence of extreme climate phases in amplifying warming and cooling signals. These findings also emphasize the critical role of ENSO teleconnections in shaping regional climate and provide insights for disaster preparedness and climate resilience in one of the world’s most vulnerable regions.