Tree-ring derived millennial precipitation record for the south-central Tibetan Plateau and its possible driving mechanism

Abstract

Knowledge of Asian monsoon variability remains limited because of sparse instrumental data available only for short time series. Here, an updated tree-ring width record covering the period ad 1037–2009 was developed for the south-central Tibetan Plateau (TP). Correlation analysis revealed a significant relationship ( r = 0.71) between the tree-ring index and annual (previous July to current June) precipitation series for the instrumental period 1963–2008, which accounts for 50.41% of the rainfall variability. Based on a linear regression model, the longest available regional precipitation history was reconstructed. Spatial correlation between tree ring width and annual precipitation data from previous July to current June indicates that the reconstruction is representative of precipitation changes on the south-central TP. Regional wet conditions occurred during ad 1095–1161, 1376–1403, 1414–1446, 1518–1537, 1549–1572, 1702–1757, 1848–1878 and 1891–1913, while dry periods were identified during ad1189–1242, 1256–1314, 1329–1357, 1470–1491, 1573–1623, 1636–1686, 1761–1821, 1823–1847, 1879–1890 and 1931–1985. The negative correlation between our reconstructed precipitation and India monsoon rainfall series indicates the seesaw pattern over northern and southern monsoon Asia. It is suggested that solar radiation-induced sea surface temperature (SST) anomalies over the tropical Pacific influence regional rainfall patterns. The degree of this influence has been stable at the multidecadal scale during the past 1000 years.

Tree ring δ18O's indication of a shift to a wetter climate since the 1880s in the western Tianshan Mountains of northwestern China

“…Similar results from tree ring δ 18 O were reported for northern Pakistan, where precipitation has been increasing since the 1860s (Figure c) and where the 20th century was the wettest century [ Treydte et al , ]. Tree ring reconstructions of hydroclimate from across High‐elevation Asia confirm intensified wet conditions in the 20th century in India [ Yadav , , ], northern Pakistan [ Treydte et al , ], Mongolia [ Davi et al , ], and the Central Tibetan Plateau [ He et al , ]. As these reconstructions were affected, at least in part, by different atmospheric circulation patterns such as the Asia Monsoon and westerly circulation, and given that moisture variations are more spatially and temporally heterogeneous than temperature changes, it is understandable that these reconstructions have no consistent variation at annual and decadal scales.…”

Linkages between climate, fire and vegetation in southwest China during the last 18.5ka based on a sedimentary record of black carbon and its isotopic composition

“…3a). This relatively wet interval has also been documented by other ISM proxies, including stalagmite δ 18 O records from Wah Shikar Cave in northeast India (Sinha et al, 2011) and Zhijin Cave in southwest China (Kuo et al, 2011), the δD record from East Rongbuk ice core in the Himalayas (Kaspari et al, 2007), and the treering record from the south-central Tibetan Plateau (He et al, 2013). The relatively wet climatic condition in the ISM region is also consistent with north China, which is influenced by the EASM (Chen et al, 2015).…”

Multi‐century tree‐ring precipitation record reveals increasing frequency of extreme dry events in the upper Blue Nile River catchment

“…The statistical characteristics of TANA chronology, such as high series intercorrelation (0.54), mean sensitivity (0.42), signal-to-noise ratio (5.3), mean EPS (0.93), and agreement with population chronology (0.84), indicate that the chronology is sensitive to climate variability and that the sampled trees respond to a common climate forcing (He, Yang, Brauning, Wang, & Wang, 2012). Strong interannual variability of tree-ring chronologies is typical for moisture- | 5445 sensitive regions (Fritts et al, 1980), indicating that the TANA chronology has captured strong common regional climate signals.…”