A bi-proxy reconstruction of Fontainebleau (France) growing season temperature from A.D. 1596 to 2000

In this paper, we develop a new methodology to estimate past changes of growing season temperature at Fontainebleau (northern France). Northern France temper- ature fluctuations have been documented by homogenised instrumental temperature records (at most 140 year long) and by grape harvest dates (GHD) series, incorporated in some of the European-scale temperature reconstructions. We have produced here three new proxy records: 18 O and 13 C of latewood cellulose of living trees and timbers from Fontainebleau Forest and Castle, together with ring widths of the same samples. 13 C data appear to be influenced by tree and age effects; ring widths are not controlled by a single climate parameter. By contrast, 18 O and Burgundy GHD series exhibit strong links with Fontainebleau growing sea- son maximum temperature. Each of these records can also be influenced by other factors such as vine growing prac- tices, local insolation, or moisture availability. In order to reduce the influence of these potential biases, we have used a linear combination of the two records to reconstruct inter- annual fluctuations of Fontainebleau growing season temper- ature from 1596 to 2000. Over the instrumental period, the reconstruction is well correlated with the temperature data (R 2 =0.60). This reconstruction is associated with an uncertainty of 1.1 C (1.5 standard deviation), and is expected to provide a reference series for the variability of growing season maxi-