The period of 5.0-3.0 ka BP (before present, present = 1950 A.D.) marks a critical transition from the midto late-Holocene, characterized by significant climate regime changes. These include the strengthening of El Niño-Southern Oscillation (ENSO) activity (Moy et al., 2002), the weakening of the East Asian Summer Monsoon (EASM) (Yuan et al., 2004), and the end of the Green Sahara period (Tierney et al., 2017). The most notable event during this period was the abrupt climate change known as the "4.2 ka BP event," which occurred from 4.2 to 3.9 ka BP and demarcated the boundary between the warmer mid-Holocene and the cooler late-Holocene (Walker et al., 2019). This abrupt climate shift is thought to have been a global-scale megadrought (Weiss, 2016) and led to the collapse of several ancient civilizations, including