Reconstruction of southeast Tibetan Plateau summer cloud cover over the past two centuries using tree ring δ18O
1Laboratoire des Sciences du Climat et de l'Environnement, UMR8212, IPSL/CEA/CNRS/UVSQ, Bat 701, L'Orme des Merisiers, CEA Saclay, 91 191 Gif sur Yvette Cedex, France
2CIRES, University of Colorado, 80309 Boulder CO, USA
3Key Laboratory for Coast and Island Development, Ministry of Education, School of Geographic and Oceanographic Sciences, Nanjing University, 22 Hankou Road, Nanjing, 210093, China
4Research center For Eco-Environment Change, Chinese Academy of Sciences, Beijing, 100085, China
Abstract. A tree-ring δ18O chronology of Linzhi spruce, spanning from AD 1781 to 2005, was developed in Bomi, Southeast Tibetan Plateau (TP). During the period with instrumental data (1961–2005), this record is strongly correlated with regional summer cloud cover, which is supported by a precipitation δ18O simulation conducted with the isotope-enabled atmospheric general circulation model LMDZiso. A 225-yr regional cloud cover reconstruction was therefore achieved. The observed cloud cover increased in the 1980s and this increase is not unprecedented in the entire reconstruction. The reconstructed cloud cover appears smaller and more stable in the 20th century than previously. A late 19th century decrease in our reconstructed cloud cover is consistent with a decrease in the TP glacier accumulation recorded in ice cores. Our data reveal a strong anomaly in the 1810s, which coincides with volcanic eruption in 1809 and the 1815 Tambora volcanic eruption.