Abstract
Drought occurrence and duration in central Asia are of important socioeconomic, ecological, and geophysical significance and have received increasing research attention in recent years. Understanding long-term drought trends and their driving forces require reliable records of past drought variability with broad spatial representativeness. Here, we compiled four tree-ring δ 18 O records from eastern central Asia (ECA) and composited them into a drought-sensitive proxy to explore regional ECA moisture variations over the past 301 years (1710–2010 CE). A robust regional standardized precipitation-evapotranspiration index (SPEI) reconstruction was established based on the tree-ring cellulose δ 18 O fractionation mechanism and statistically significant proxy-climate relationships. We identified prominent droughts in 1710–1770, 1810–1830, and the beginning of the twenty-first century, and a regime shift to a persistently wet period from the 1880s to 2000. Our reconstruction reveals the impact of drought and pluvial patterns on the decline of Zhungar Empire, and on historical agricultural and socio-economical activities, including increased migration into ECA during the 1770–1800 pluvial. Our findings also suggest that wet conditions in the twentieth century in ECA were related to a strengthening of the westerly circulation and thus shed light on large-scale atmospheric circulation dynamics in central Asia.
Original language | English (US) |
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Pages (from-to) | 713-727 |
Number of pages | 15 |
Journal | Climate Dynamics |
Volume | 52 |
Issue number | 1-2 |
DOIs | |
State | Published - Jan 24 2019 |
Keywords
- Drought reconstruction
- Eastern Central Asia
- SPEI
- Stable oxygen isotopes
- Tree rings
ASJC Scopus subject areas
- Atmospheric Science