Prolonged drought on Rapa Nui during the decline of megalithic monument construction

Drought may have contributed to changes in human geography on Rapa Nui in the late 16th and early 17th centuries, but there are currently no continuous paleoclimate records that provide direct, quantitative insight into local hydroclimate conditions during this time period. Here, we present new evidence for a multicentury rainfall deficit on Rapa Nui beginning at approximately 1550 CE, based on two independent reconstructions of hydrogen isotopes in rainfall inferred from hydrogen isotopes in leaf waxes preserved in wetland sediments. Chain-length distribution data suggests that known vegetation changes on Rapa Nui (e.g., palm deforestation) did not significantly influence the sources of leaf waxes for either wetland. Therefore, we assume that leaf wax hydrogen isotopes reflect isotopes in precipitation at a constant offset through time. We use instrumental data from the Global Network of Isotopes in Precipitation (GNIP) to show that there is a significant relationship between isotopes ..., , # Data from: Prolonged drought on Rapa Nui during the decline of megalithic monument construction

## Description of the data and file structure

Data.xlsx contains all leaf wax hydrogen isotope and chain-length distribution data files for sediment cores from Rano Aroi wetland and Rano Kao crater lake. All sheets are separately provided as CSVs under the same titles. The variable descriptions below are broken up by dataset.

### **Variable Descriptions** 

**Data file: Rano_Kao_Hydrogen_Isotopes.csv**

*Variable:* Depth (cm)
*Description:* Depth of each sample in core KAO08-03. Depths are listed as the midpoint between the top and bottom of the sampling interval.

*Variable:* Year (CE)
*Description:* Modeled age of the sediment at each sample depth. See the Sharing/Access Information section for more information on the KAO08-03 age-depth model.

*Variable:* Max Age (CE)
*Description:* Maximum age of the sediment at each depth, defined as the upper 95 % confidence interval of the age-dep...,