Precipitation reconstruction from Hailar pine ( Pinus sylvestris var. mongolica) tree rings in the Hailar region, Inner Mongolia, China back to 1865 AD

Abstract

Precipitation is the major limiting factor for the radial growth of Hailar pine ( Pinus sylvestris var. mongolica) in the Hailar, northeast China. Herein, the amount of precipitation from the previous July to current June was chosen for reconstruction from 1865 to 2003 AD. This reconstruction accounts for 51% of the variance in the instrumental precipitation data during the 1952–2003 period. The reconstruction reveals the precipitation fluctuation history over the last 139 years. Some severe drought events (lasting for more than 3 years) are displayed in the series, such as 1905–1909, 1926–1929 (a severe drought event in central-northern China with tremendous losses of human lives) and 1968–1970; extreme wet events are 1867–1870, 1932–1934, 1939–1941 and 1955–1957. On the decadal scale, there are two dry periods (with precipitation lower than the mean of 1865–2003): 1888–1929 and 1963–1975, and two wet intervals (more than the mean): 1930–1962 and 1976–2003. Drought events or dry intervals correspond to weak, and wet events to strong, East Asian Summer Monsoon (EASM). The reconstructed precipitation can be well compared with the Baiyinaobao, Ortindag Sand Land in eastern Inner Mongolia and northeastern Mongolia rainfall series derived from tree rings. The four curves show similar variation related to weak/strong EASM. A power spectrum analysis shows that there are 7.67- and 7.08-year quasi-periodicities, which may be associated with ENSO activity.