Sampling strategy and climatic implications of tree-ring stable isotopes on the southeast Tibetan Plateau     

Chunming Shi  Valérie Masson-Delmotte  Camille Risi  Thomas Eglin  Michel Stievenard  Monique Pierre  Xiaochun Wang  Jing Gao  François-Marie Bréon  Qi-Bin Zhang  Valérie Daux 《Earth and Planetary Science Letters》2011,301(1-2):307-316

We explore the potential of tree-ring cellulose δ¹⁸O and δ¹³C records for reconstructing climate variability in the southeast Tibetan Plateau. Our sampling strategy was designed to investigate intra and inter-tree variability, and the effects of the age of tree on δ¹⁸O variation. We show that intra-tree δ¹³C and δ¹⁸O variability is negligible, and inter-tree coherence is sufficient to build robust tree-ring δ¹⁸O or δ¹³C chronologies based on only four trees. There is no evidence of an age effect regarding δ¹⁸O, in contrast with tree-ring width. In our warm and moist sampling site, young tree δ¹³C is not clearly correlated with monthly mean meteorological data. Tree-ring δ¹⁸O appears significantly anti-correlated with summer precipitation amount, regional cloud cover, and relative humidity. Simulations conducted with the ORCHIDEE land surface model confirm the observed contribution of relative humidity to tree cellulose δ¹⁸O, and explain the weak correlation of δ¹³C with climate by the non-linear integration linked with photosynthesis. Altogether, the tree-ring cellulose δ¹⁸O is shown to be a promising proxy to reconstruct regional summer moisture variability prior to the instrumental period.  相似文献   

Grapevine harvest dates in Besan?on (France) between 1525 and 1847: Social outcomes or climatic evidence?     

E. Garnier  V. Daux  P. Yiou  I. Garc��a de Cort��zar-Atauri 《Climatic change》2011,104(3-4):703-727

We present a unique contextualised series of grape harvest dates (GHD) from Besançon, Eastern France, from the early sixteenth to the mid nineteenth century. The GHD series was processed to remove as far as possible health-medical and socio-political influences. It is well correlated with temperature indices determined from other documentary sources. However, we find that the relation between the GHD-series and the occurrence of meteorological processions is not convincing. At the inter-annual scale the Besançon GHD-series is highly correlated with the corresponding GHD-series from Germany, Switzerland and Burgundy (France) and to instrumental temperature series from England and the Netherlands. On the other hand, the series are not correlated to one another at the multidecadal scales. The origins of this decoupling remain to be elucidated.  相似文献   

Summer maximum temperature in northern France over the past century: instrumental data versus multiple proxies (tree-ring isotopes, grape harvest dates and forest fires)     

N. Etien  V. Daux  V. Masson-Delmotte  O. Mestre  M. Stievenard  M. T. Guillemin  T. Boettger  N. Breda  M. Haupt  P. P. Perraud 《Climatic change》2009,94(3-4):429-456

Changes in maximum spring and summer temperature are expected to have impacts on plant phenology and the occurrence of forest fires. Homogenised instrumental records of maximum spring and summer temperature are available in northern France for the past century, as well as documentary records of grape harvest dates and forest fire frequencies. Here we provide a new proxy of seasonal climate obtained by the analysis of latewood tree ring cellulose isotopic composition (δ¹⁸O, δ¹³C and δD), from 15 living oak trees (Quercus petraea) sampled in the Fontainebleau forest, near Paris. For the past 30 years, we have conducted a study on the inter-tree (for oxygen isotopes) and inter-station (for oxygen and hydrogen) isotopic variability. Multiple linear regression statistical analyses are used to assess the response function of documentary and tree-ring isotopic records to a variety of climatic and hydrological parameters. This calibration study highlights the correlation between latewood tree-ring δ¹⁸O and δ¹³C, grape harvest dates and numbers of forest fire starts with maximum growing season (April to September) temperature, showing the potential of multiple proxy reconstructions to assess the past fluctuations of this parameter prior to the instrumental period.  相似文献   

Unprecedented recent warming rate and temperature variability over the east Tibetan Plateau inferred from Alpine treeline dendrochronology     

Shi  Chunming  Masson-Delmotte  Valérie  Daux  Valérie  Li  Zongshan  Carré  Matthieu  Moore  John C. 《Climate Dynamics》2015,44(5-6):1367-1379

Climate Dynamics - Despite instrumental records showing recent large temperature rises on the Tibetan Plateau (TP), only a few tree-ring temperature reconstructions do capture this warming trend....  相似文献