Hydrometeorological Reconstructions for Northeastern Mongolia Derived from Tree Rings: 1651–1995

Abstract

Reconstructions of annual (prior August?current July) precipitation and streamflow, 345 yr in length (1651?1995), are presented for northeastern Mongolia based on tree-ring width data. These precipitation and streamflow reconstructions account for 54% and 48% of the respective variance in instrumental data over the past 50 years. Variations in instrumental precipitation and streamflow are within the range of those reconstructed over the length of tree-ring records. However, there appear to be more frequent extended wet periods during the twentieth century. Multitaper spectral analysis revealed statistically significant peaks at 10.8 and 12.8 yr for the precipitation reconstruction, and at 12.8 and 20.3?23.8 yr for the streamflow reconstruction. Similarly, singular spectrum analysis identified spectral modes of variation at 12 and 21 yr for both series. These spectra resemble those found for tree-ring-based precipitation reconstructions in central China as well as the western United States, and may reflect solar influences on the climate of Mongolia.