In general, it is known that extreme climatic conditions such as El Niño and positive Indian Ocean Dipole (IOD+) cause prolonged drought in Indonesia's tropical peatlands so that groundwater levels (GWL) drop and peat is prone to fire. However, 27 years of GWL measurements in Central Kalimantan peat forests show the opposite condition, where the lowest GWL occurs several weeks before El Niño and after IOD+ reaches its peaks. We show that the dropped sea surface temperature anomaly induced by anomalously easterly winds along the southern Java-Sumatra occurs several weeks before the GWL drop to the lowest value. Local rainfall decreased, and GWL dropped sharply by 1.0 to 1.5 m, during the super El Niño events in 1997/98 and 2015, as well as remarkable events of IOD+ in 2019. It is suggested that the tropical peatland ecohydrological system (represented by the GWL), El Niño Southern Oscillation (ENSO), and IOD+ are teleconnected. Hence, monitoring GWL variability of peatland over the IMC is a possibility an alert for extreme climate events associated with El Niño and/or moderate IOD+.
- Authors: Sulaiman, A., Osaki, M., Takahashi, H., Yamanaka, M.D., Susanto, R.D., Shimada, S., Kimura, K., Hirano, T., Wetadewi, R.I., Sisva, S., Kato, T., Kozan, O., Kubo, H., Awaluddin, A., Tsuji, N.
- Author Affiliation: National Research and Innovation Agency, Hokkaido University, Research Institute for Humanity and Nature, University of Maryland, Diponegoro University, Tokyo University of Agriculture, Nara University, Peatland and Mangrove Restoration Agency, PT Wana Subur Lestari/PT Mayangkara Tanaman Industri, Sumitomo Forestry Co. Ltd., Kyoto University, Institute for Global Environmental Strategies, NPO FutureForest Institute
- Subjects: El Nino-Southern Oscillation; Groundwater; Indian Ocean; Indonesia; Seasons; Soil; ground water; El Nino; Indian Ocean; Indonesia; season; soil
- Publication type: Journal Article
- Source: Scientific Reports 13(1): 939
- Year: 2023
- DOI: https://doi.org/10.1038/s41598-023-27393-x