High-resolution reconstruction of typhoon events since ~1850 CE based on multi-proxy sediment records in a coastal lagoon, South China

Abstract

Coastal lagoon sediments provide continuous and high-resolution records of the activity of past typhoons. In this study, multiple proxies were analyzed with a core taken from Pinqing Lagoon located on the northeast margin of the South China Sea. Based on ²¹⁰Pb dating, grain sizes and other geophysical/geochemical analyses, a total of seven typhoon-induced layers covering the past ~170 years were identified and compared with observational and historical records of typhoons. The layers were characterized by a higher sand fraction, lower loss-on-ignition, decreased magnetic susceptibility, and increased element ratios of Sr/Fe, Sr/Ba, Ca/Ti, and Ca/K. We found reduced sensitivity of the sedimentary response to typhoons due to the coastal geomorphological evolution, such as sand spit growth, which emphasizes the value of using a multiple-proxy approach. The typhoon activity revealed by both sedimentary proxies and observational/historical records in Shanwei was closely related to the variations of the El Niño/Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and to sunspot activity, providing useful clues for reconstructing the long-term typhoon history in the lagoon in order to decipher the patterns and mechanisms of typhoons in South China.

Keywords: Coastal geomorphology; Pinqing Lagoon; Sedimentary proxy; Typhoon history.