Annual variation in PDSI since 1897 AD in the Tengger Desert, Inner Mongolia, China, as recorded by tree-ring data

摘要

Tree-ring data can be used to provide high-resolution records of climate variability in areas like the Tengger Desert where few other records exist. In the present work, three tree-ring-width chronologies in the Luoshan Mountains in north-western China showed synchronous variation. These were averaged to develop a comprehensive chronology that was then used to reconstruct the Palmer Drought Severity Index (PDSI) since 1897 AD for the grid point N 38°45′, E 103°45′ in the Tengger Desert. The annual PDSI and tree-ring widths in the Changlingshan Mountains at the southern margin of the Tengger Desert matched well (r = 0.50, p ＜ 0.001), indicating the reliability of the reconstruction. The annual PDSI dry and wet periods were consistent with recorded lake sediments in the northern Mu Us Desert. The dry periods in the Tengger Desert were compatible with the relatively low PDSI in the Ortindag Sand Land in eastern Inner Mongolia. Abrupt climate variability occurred around 1922,1933,1934,1935 and 1936, in line with abrupt changes in the Asian monsoon system in the 1930s. Distinct periods of about 2-4 years and 5-7 years were evident in the reconstructed PDSI.