Geographia Technica, Vol 20, Issue 2, 2025, pp. 319-335
COMPARISON OF Triple-Dip LA NIÑA IN 2020-2023 WITH STRONG AND WEAK LA NIÑA EVENTS ON INDONESIAN RAINFALL AND SST
Gangga Dara DESTYANO 
, Anindya WIRASATRIYA , Muhammad ZAINURI , Yusuf Jati WIJAYA , Bayu MUNANDAR , Muhammad HELMI
ABSTRACT: The Triple-Dip La Niña event that occurred from 2020 to 2023 was a rare phenomenon characterized by enhanced convection and extreme rainfall. This study aims to quantify and compare rainfall and SST during different La Niña conditions, and to analyze the factors driving rainfall variability over these events. This research examines three La Niña events: Triple-Dip (2020-2023), strong (2010-2011), and weak La Niña (2017-2018), within Indonesia, located between 6°N-11°S and 95°E-141°E. In this study, satellite-based rainfall, SST and surface wind data served as primary data sources, which were analyzed using anomaly map. Triple-Dip and strong La Niña events exhibit similar spatial patterns of anomalies in rainfall and sea surface temperature (SST). During the JJASON period, these phenomena led to increased rainfall across much of Indonesia, including regions such as Sumatra, Western and Central Kalimantan, Sulawesi, parts of Maluku, Papua, Western Java, the waters off western Sumatra, the Natuna Sea, Java Sea, Banda Sea, and Arafura Sea. This season also saw a rise in SST throughout most of Indonesia. Conversely, during the December to May period, Triple-Dip and strong La Niña resulted in reduced rainfall in areas like Sumatra, Java, Kalimantan, Sulawesi, Maluku, and Papua, along with a decrease in SST in the Natuna Sea, Java Sea, Flores Sea, and the Indian Ocean, from the western waters of Sumatra to the southern waters of Java. In contrast, weak La Niña events displayed a more scattered pattern of rainfall anomalies, though the SST anomaly distribution was largely similar to that of Triple-Dip and strong events, except during June-August. During June-August, weak events showed a decline in SST in the Southern Java Sea. The increase in rainfall during La Niña events was particularly notable during June-November, attributed to the elevated SST across most of Indonesia.
Keywords: Triple-Dip La Niña; Rainfall; Sea Surface Temperature, Indonesia.
Full article here