ANALYSIS OF THE INFLUENCE OF WEATHER AND CLIMATE ON THE UPWELLING PHENOMENON ALONG THE SOUTHERN COAST OF JAVA DURING THE 2011-2020 PERIOD

The upwelling phenomenon is one of the important oceanographic processes that has a major impact on marine productivity. The southern coastal area of Java is known as an area that is prone to seasonal upwelling, especially during the east monsoon period. However, the dynamics of upwelling in this area are greatly influenced by the complex interaction between weather and climate factors, such as monsoon winds, sea surface temperature (SST), salinity, ocean currents, and global climate phenomena such as ENSO. This study aims to analyze the upwelling phenomenon with the distribution of chlorophyll-a (plankton) concentrations as a biological indicator, as well as with weather and climate parameters to understand the relationship between variables holistically. In addition, this study also aims to correlate the effects of weather and climate on the intensity of the upwelling phenomenon. The method used is the stepwise method with spatial and temporal analysis based on secondary data. The data used include sea surface temperature, wind direction and speed, ocean currents, salinity, ENSO index, and zooplankton concentration during the period 2011–2020. The analysis was carried out using MATLAB for spatial mapping and time series visualization. The results of the analysis show that upwelling tends to occur during the east monsoon and is associated with a decrease in sea surface temperature, an increase in zooplankton concentration, and a dominant southeast wind direction. Sea surface temperature (SST) and wind are the most significant predictors in triggering upwelling, while ENSO acts as a strengthener or weakener of its intensity. The conclusion of this study shows that weather and climate dynamics significantly influence the occurrence of upwelling on the southern coast of Java. Understanding this phenomenon is important in supporting sustainable and adaptive management of marine resources to global climate change.

Keywords: Upwelling, Zooplankton, Sea Surface Temperature (SST), Monsoon