Moisture increase in response to elevated high-altitude warming evidenced by tree-rings on the southeastern Tibetan Plateau

Abstract:

Marked increase in global temperature has been observed since the early twentieth century. However, this warming is not spatially uniform, with a large percentage of rapid warming rates found over the high-altitude areas. The Tibetan Plateau (hereafter, TP) experienced a rapid temperature increase during the instrumental era. The effects of TP warming are dramatic and widespread, such as glacial and permafrost melting, sea level rise, water resources depletion, and vegetation change. Among them, the implications on moisture change at regional and global scale is poorly understood, and one critical reason is the lack of extensive, long-term observations in the high-elevation areas. Here we use tree-rings to reveal common moisture change on the southeastern TP for the past five centuries, and show that regional moisture change in late spring and early summer (April-June) has been closely related to large-scale temperature anomaly on the TP, with increased moisture coinciding with higher temperature. This relationship alone implies generally wetter conditions on the southeastern TP under future global warming.