Last Millennium temperature variability and onset of industrial-era warming in the Eastern Tibetan Plateau

Category: Time:
Wednesday, November 28, 2018 - 11:45 to 13:00
Room: Speaker:
Guobao Xu
David Frank

The Tibetan Plateau (TP), also named the “Third Pole”, plays an important role in the Asian Monsoon system and atmospheric circulation of the Northern Hemisphere. How unprecedented is the recent warming in the TP when we place it in the last millennium context? Did abnormal climate change periods, such as the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA), occur in TP? If so, when did the MCA-LIA transition occur? When did the onset of significant and sustained industrial-era warming occur? In this talk, I will introduce my work progress in this year.
In this study, we developed two tree-ring based temperature reconstructions for the northeastern and southeastern TP by synthesizing the recent published temperature reconstruction data. We also compared the reconstructions with CMIP5 climate model simulations. Our results highlight the following features:

  1. TP temperature shows a warm MCA and a cool LIA. The MCA-LIA transition (ca. 1587 CE) happened about 150 years later in our TP reconstructions compared to other larger-scale temperature reconstructions.
  2. Our reconstructions show unprecedented industrial-era warming, the onset of which is 30 to 40 years earlier in northeastern TP (ca. 1812 CE) than in other regions and in model simulations. The earlier onset of industrial-era warming may relate to the higher warming rate in this region.
  3. The Atlantic Multidecadal Oscillation (AMO) affects TP temperature variability, especially in the southeast. A warm to cool AMO transition resulted in southeastern TP cooling in the 1960s-1980s.