Tree-ring width based streamflow reconstruction for the Kaidu River originating from the central Tianshan Mountains since A.D. 1700

Abstract

In this study, a 310-year pSeptember–August record of streamflow (where p denotes a month from the previous year) for the Kaidu River was reconstructed based on tree-ring-width from 137 Schrenk spruces (Picea schrenkiana). Spatial correlation showed that this streamflow reconstruction contains local hydroclimatic signals that approximately overlap the Kaidu River watershed. A comparison between the streamflow reconstruction for the Kaidu River and five tree-ring-based hydrological reconstructions for the surrounding areas revealed similar variations in the low-frequency domain. The results of comparison analyses between this reconstruction and other hydrological reconstructions indicated that the hydrological characteristics of the Kaidu River in the 1910s (the driest decade for the Kaidu River in the last 310 years), and the increasing trend of streamflow that began in the 1980s, might have occurred in other areas of the Tianshan Mountains and covered an even larger area. Furthermore, the highest and lowest values of this reconstructed streamflow series capture five flood or snowfall events (1803, 1804, 1836, 1923, and 1959) and six drought events (1894, 1916, 1917, 1918, 1931, and 1944) that were noted in historical documents. The 10.8- and 3.5–5.4-year cycles of this reconstruction coincided with the observed data and other tree-ring based hydrometeorological reconstructions, and revealed the possible influences of solar activity and the atmosphere–ocean system.