Are the oxygen isotopic compositions of Fitzroya cupressoides and Nothofagus pumilio cellulose promising proxies for climate reconstructions in northern Patagonia ? Lavergne, A. Daux, V. Villalba, R. Pierre, M. Stievenard, M. /Vimeux, Françoise Srur, A. M. north Patagonia cellulose O-18 Fitzroya cupressoides Nothofagus pumilio climate change Tree ring O-18 chronologies from two native species (Fitzroya cupressoides and Nothofagus pumilio) in northern Patagonia were developed to assess their potential for paleoclimate reconstructions. The five annually resolved cellulose O-18 chronologies (two for F. cupressoides and three for N. pumilio) are located on the Andes along the steep west-to-east precipitation gradient. Over the common 60years long interval, the five site-O-18(cell) chronologies exhibit a strong common signal as indicated by the significant mean intercorrelation (r=0.61, p<0.05) and the high percentage (65%) of total variance explained by the first empirical orthogonal function. Although correlation analyses reveal that the two mean species-O-18(cell) chronologies are mainly modulated by December-May temperature, the N. pumilio chronology shows a greater sensitivity to record temperature variations (r=0.57, p<0.05). The O-18(cell) of N. pumilio contains a regional temperature signal representative of a large area in southern South America under the influence of the Southern Annular Mode. This study indicates that O-18(cell) in N. pumilio is a promising proxy to reconstruct past variations in temperature in South America south of 38 degrees S. 2016 text https://www.documentation.ird.fr/hor/fdi:010066809 fdi:010066809 Lavergne A., Daux V., Villalba R., Pierre M., Stievenard M., Vimeux Françoise, Srur A. M.. Are the oxygen isotopic compositions of Fitzroya cupressoides and Nothofagus pumilio cellulose promising proxies for climate reconstructions in northern Patagonia ?. 2016, 121 (3), 767-776 EN ARGENTINE CHILI ANDES