Extended Data Fig. 3: Warm-season temperature reconstruction skill of A-FEN and X-FEN, as well as comparisons with existing large-scale reconstructions and regional climate simulations but using QWA data that has not been detrended using the RCS approach.
From: Fennoscandian tree-ring anatomy shows a warmer modern than medieval climate
The non-QWA datatypes are identical to Fig. 2 of the Main manuscript and the vertical arrows have the exact positions and dimensions as in Fig. 2 for reference. a) A-FEN (produced in this study) calibrated using regional mean air MJJA temperatures68 (R2 ensemble range within brackets (a = 0.05)), and results for the X-FEN (from Wilson, et al.9) using corresponding JJA temperatures. The irregular winter/spring of 1902/1903, led to a massive dieback of yearly branch-shoots in the region55, highlighted by the yellow area. In these years with extremely narrow rings, the X-ray technique struggles to measure high MXD values due to its comparatively lower effective measurement resolution29 (see Extended Data Fig. 4). b) Replication and pairwise inter-series correlation (\(\bar{R}\)) of A-FEN in blue and the X-FEN in red. c) Centennial-scale variations (see Methods) compared between A-FEN, X-FEN, climate model simulations, and NH and global temperature reconstructions. The five large-scale reconstructions1,9,10,38,39, as well as the eleven regionally extracted climate-model simulations40,41,42,43,44,45,46,47,48,49,50 are represented by probabilistic percentile ranges. The vertical arrows highlight the overall discrepancies of the X-FEN compared to the other data.
