Forward modeling analysis of regional scale tree-ring patterns around the northeastern Tibetan Plateau, Northwest China

Abstract

Abstract. The process-based Vaganov–Shashkin (VS) model was used to simulate regional patterns of climate-tree growth relationships linking daily length, temperature and precipitation from meteorological data (AD 1957–2000) over the northeastern Tibetan Plateau (TP). The results exhibit that the leading principle component of the hypothetical growth curves is broadly consistent with that of the actual tree-ring chronologies, demonstrating the interpretability of the simulations as an accurate representation of the climatic controls on tree growth of Qilian Juniper. Output from this model both agrees well with the statistical relationships between tree-ring growth and climate factors as well as observational physiological behavior, i.e. precipitation in June acts as the most contributing role in annual ring formation of Qilian Juniper over the northeastern TP. The non-stationary and nonlinear response of tree growth to climate variability has important implications for calibration of tree-ring records for paleoclimate reconstructions and prediction for forest carbon sequestration.