Affiliation:
1. College of Resource, Environment and Tourism, Capital Normal University, China
2. Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, China
Abstract
Climate changes on different timescales and their mechanisms are of great importance in arid Central Asia (ACA). However, the contribution of El Niño−Southern Oscillation (ENSO) to Holocene hydroclimate in ACA on centennial and millennial timescales is limited by records with good age control and high temporal resolution. Here, we present high-resolution X-ray fluorescence (XRF) scanning data of a sediment core from Lake Xiaolongchi in central Tianshan Mountains to reconstruct hydroclimate changes in ACA over the last 8000 years. Our construction exhibits that the climate was dry from 8000 to 5500 cal year BP and wet from 5500 to 0 cal year BP, which resembles ENSO patterns on a millennial timescale. On the centennial timescale, hydroclimate fluctuations with eight wet periods, seven dry periods, and a shift period have a significant 800-year periodicity, coincident with periodic ENSO variance. The positive relationship between 800-year band-pass filtered hydroclimate and ENSO indicates that wet (dry) climate conditions correspond to increased (reduced) ENSO activity. We propose that the spatial pattern of “wet (dry) southern China and ACA, and dry (wet) northern China” during the El Niño-like (La Niña-like) condition may exist during the Holocene on millennial to centennial timescales.
Funder
National Key Research and Development Program of China
Basic Research Program of the Institute of Hydrogeology and Environmental Geology CAGS
National Natural Science Foundation of China
Subject
Paleontology,Earth-Surface Processes,Ecology,Archeology,Global and Planetary Change