Research Center for Climate and Atmosphere, National Research and Innovation Agency, Bandung, Indonesia.
Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan.
Sci Rep. 2023 Jan 18;13(1):939. doi: 10.1038/s41598-023-27393-x.
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+.
一般来说，众所周知，厄尔尼诺和印度洋偶极子正位相（IOD+）等极端气候条件会导致印度尼西亚热带泥炭地长期干旱，从而导致地下水位（GWL）下降，泥炭易发生火灾。然而，在加里曼丹中部泥炭林进行的 27 年地下水位测量显示出相反的情况，即地下水位最低出现在厄尔尼诺之前和 IOD+达到峰值之后的几周。我们表明，在 GWL 降至最低值之前的几周，异常东风引起的海面温度异常下降发生在沿爪哇-苏门答腊南部。当地降雨量减少，地下水位在 1997/98 年和 2015 年的超强厄尔尼诺事件以及 2019 年的显著 IOD+事件中急剧下降了 1.0 至 1.5 米。这表明热带泥炭地生态水文学系统（以 GWL 表示）、厄尔尼诺南方涛动（ENSO）和 IOD+存在遥相关。因此，监测 IMC 上泥炭地的 GWL 变化是一种可能的极端气候事件（与厄尔尼诺和/或中度 IOD+相关）的预警。
