A comparison of tree-ring records and glacier variations over the past 700 years, northeastern Tibetan Plateau

Abstract

The ecological environment of the headwater area of the Yellow River, west China, is seriously deteriorating because of the harsh natural environment, weakened ecological system and intensified human activities as well as regional climate changes. Forests and glaciers coexist in this area. Glaciers in the area have retreated over the last decade because of climate change. Most glaciers on the Tibetan Plateau (TP) tend to retreat during warm intervals and advance during cold intervals. Tree-ring records provide an important index for examining past climate changes. A total of 139 core samples from 97 living cypresses (Juniperus przewalskii) in the central region of the Yelllow River headwater area, the Animaqin mountains, northeastern TP, were sampled from three site that are close to each other. The chronologies were developed using the ARSTAN program. Analyse indicate that these tree-ring width records reflect the summer maximum temperature of the study area over the past 700 years. The tree-ring records and the glacier advances recorded by terminal moraines are compared. Inferred summer maximum temperatures suggest three cold periods during the Little Ice Age, around AD 1500, 1700 and 1850. These cold intervals are consistent with the glacier moraine record from the region.