Fig. 3: Relationship between fire emissions and climate anomalies.

Mean May–September GFED4.1s CO₂ + CO fire emissions as a function of May–September T2M Z-score and January–September precipitation Z-score for each 0.5° × 0.625° forested grid cell during 2003–2023 (using 2003–2022 as a baseline). For individual years, the mean Z-scores across forested grid cells are shown with ‘X’. The projected decadal-mean temperature and precipitation Z-scores for the median CMIP6 model under SSP 2–4.5 are shown by the circles. The CMIP6 Z-scores are calculated using the 2000–2019 period as a baseline but use the reanalysis 2003–2022 standard deviations (see section on ‘Climate data’). The historical and projected T2M and precipitation over the Canadian boreal forests simulated by the CMIP6 ensemble are shown in Supplementary Fig. 12.