Reconstruction of ENSO variability using the standardized growth index of a Tridacna shell from Yongshu Reef, South China Sea

• DOI: 10.5194/egusphere-egu24-21421
• Publication Date: 2024-03-11T14:48:41Z
• Authors: Jun Geng; Hong Yan; Chengcheng Liu; Tao Han; Shan Liu; Nanyu Zhao; Hanfeng Wen; Haotian Yang; Pengchao Zhou; Guozhen Wang; John Dodson

El Niño-Southern Oscillation (ENSO) is the strongest signal of global interannual climate anomaly and reconstructing past ENSO variations using high-resolution paleoclimate archives can improve our understanding variability, as well ability to predict future changes. Here, a daily resolution standardized growth index (SGI) was established giant clam (Tridacna spp.) shell specimen MD2 (life span: AD 1994-2013), collected from Yongshu Reef, southern South China Sea (SCS). The cross-spectral correlation analysis indicated that SGI variation strongly influenced by variability on an timescale. Tridacna spp. in symbiosis with zooxanthellae, its usually modulated photosynthetic efficiency zooxanthellae. During Niño (La Niña) period, convective anomalies stimulated western Pacific would increase (decrease) effective solar radiation turn influence photosynthesis rate zooxanthellae enzyme activity for calcification site thus MD2. explain 54.7% variance, demonstrating potential reconstruction. Compared conventional reconstruction geochemical proxies, method rapid economical.