Unstable relationships between tree ring δ18O and climate variables over southwestern China: possible impacts from increasing central Pacific SSTs
In this study, we investigated the potential influence of central and eastern Pacific sea surface temperatures (SSTs) on the unstable relationship between earlywood δ18O and climatic factors in the southwestern China from 1902 to 2005. The results show that the strength of the climate signals recorded in the earlywood δ18O series has declined since the late 1970s. This reduction in signal strength may have been caused by the changes in the local hydroclimate, which is associated with the increasing SSTs in the central Pacific Ocean over recent decades. Alongside these increasing SSTs in the central Pacific, southwestern China has experienced more droughts, as well as more severe droughts through the late spring and early summer during the central Pacific (CP) El Niño years than during the eastern Pacific (EP) El Niño years in recent decades. This increased drought frequency may have weakened the response of earlywood δ18O to climate variables.
We gratefully acknowledge the journal editor and anonymous reviewers for their constructive comments on earlier versions of this manuscript. Many thanks are due to the National Climatic Data Center (NCDC), the National Center for Atmospheric Research (NCAR), the Climate Research Unit (CRU), and the Global SPEI database for providing the relative gridded data, as well as the Royal Netherlands Meteorological Institute (KNMI) website for providing the relative spatial correlation analysis used in this study.
This research was supported by the National Natural Science Foundation of China (41401219, 415711961, 41630529, and 41690114), the fundamental Research funds for the Central Universities (Projects No, GK201801007) and by the Knowledge Innovation Project of the Chinese Academy of Sciences (29Y329B91).
- Bale RJ, Robertson I, Leavitt SW, Loader NJ, Harlan TP, Gagen M, Young GHF, Csank AZ, Froyd CA, McCarroll D (2010) Temporal stability in bristlecone pine tree-ring stable oxygen isotope chronologies over the last two centuries. The Holocene 20(3):3–6. https://doi.org/10.1177/0959683609348867 CrossRefGoogle Scholar
- Coppola A, Leonelli G, Salvatore MC, Pelfini M, Baroni C (2012) Weakening climatic signal since mid-20th century in European larch tree-ring chronologies at different altitudes from the Adamello-Presanella Massif (Italian Alps). Quat Res 77:344–354. https://doi.org/10.1016/j.yqres.2012.01.004 CrossRefGoogle Scholar
- Fang K, Gou XH, Chen FH, Li J, D’Arrigo R, Cook E, Yang T, Davi N (2009) Reconstructed droughts for the southeastern Tibetan Plateau over the past 568 years and its linkages to the Pacific and Atlantic Ocean climate variability. Clim Dyn 35:577–585. https://doi.org/10.1007/s00382-009-0636-2 CrossRefGoogle Scholar
- Liu JH, Wen KG (2006) Meteorological disaster in China. Yunnan Province China Meteorological Press, BeijingGoogle Scholar
- Mass CF, Portman DA (1989) Major volcanic eruptions and climate: a critical evaluation. J Clim 2:566–593. https://doi.org/10.1175/1520-0442(1989)002<0566:MVEACA>2.0.CO;2 CrossRefGoogle Scholar
- Myers CG, Jessica LO, Sharp WD, Bennartz R, Kelley NP, Covey AK, Breitenbach SFM (2015) Northeast Indian stalagmite records Pacific decadal climate change: implications for moisture transport and drought in India. Geophys Res Lett 42(10):4124–4132. https://doi.org/10.1002/2015GL063826 CrossRefGoogle Scholar
- Palmer WC (1965) Meteorological drought. In: White RM (ed) Weather Bureau Research, paper 45. US Department of Commerce, Washington DCGoogle Scholar
- Quinn WH, Neal VT (1992) The historical record of El Niño events. In: Bradley RS, Jones PD (eds) Climate since AD 1500. Routledge, London, pp 623–648Google Scholar
- Shi C, Daux V, Li Z, Wu X, Fan T, Ma Q, Wu X, Tian H, Carré M, Ji D, Wang W, Rinke A, Gong W, Liu Y, Chen Y, Masson-Delmotte V (2018) The response of relative humidity to centennial-scale warming over the southeastern Tibetan Plateau inferred from tree-ring width chronologies. Clim Dynam. https://doi.org/10.1007/s00382-018-4107-5
- Tsuji H, Nakatsuka T, Yamazaki K, Takagi K (2008) Summer relative humidity in northern Japan inferred from δ18O values of the tree ring in (1776–2002 A.D.): influence of the palaeoclimate indices of atmospheric circulation. J Geophys Res 113:D18103. https://doi.org/10.1029/2007JD009080 CrossRefGoogle Scholar
- Xu GB, Liu XH, Wu GJ, Chen T, Wang WZ, Zhang Q, Zhang YF, Zeng XM, Qin DH, Sun WZ, Zhang XW (2015) Tree-ring δ18O indicates a shift to a wetter climate since the 1880s in the western Tianshan Mountains of northwestern China. J Geophys Res 120:6409–6425. https://doi.org/10.1002/2014JD023027 CrossRefGoogle Scholar
- Yang YL, Du Y, Chen HS, Zhang YS (2011) Influence of ENSO event on rainfall anomaly over Yunnan Province and its neighboring regions during late spring-early summer. Chin J Atmos Sci 35(4):729–738 (in Chinese with English abstract)Google Scholar
- Zhao RZ (1997) A study of the physico-geographical regionalization in southwest region. J Southwest China Normal Univ 22(2):193–198 (in Chinese)Google Scholar