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Departures from historical wildfire regimes due to climate change have significant implications for the structure and composition of forests, as well as for fire management and operations in the Alberta region of Canada. This study analyzed the relationship between climate and wildfire and used a random forest algorithm to predict future wildfire frequencies in Alberta, Canada. Key factors driving wildfires were identified as vapor pressure deficit (VPD), sea surface temperature (SST), maximum temperature (Tmax), and the self-calibrated Palmer drought severity index (scPDSI). Projections indicate an increase in wildfire frequencies from 918 per year during 1970–1999 to 1151 per year during 2040–2069 under a moderate greenhouse gas (GHG) emission scenario (RCP 4.5) and to 1258 per year under a high GHG emission scenario (RCP 8.5). By 2070–2099, wildfire frequencies are projected to increase to 1199 per year under RCP 4.5 and to 1555 per year under RCP 8.5. The peak number of wildfires is expected to shift from May to July. These findings suggest that projected GHG emissions will substantially increase wildfire danger in Alberta by 2099, posing increasing challenges for fire suppression efforts. [ABSTRACT FROM AUTHOR]

Tree‐ring blue intensity (BI) is well known as a relatively new proxy, which has been utilized for temperature reconstructions over some regions of the worldwide, and has great research potential. In this study, based on tree‐ring data from Pinus massoniana in northwestern Wuyi Mountains in southeastern China, we established a series of tree‐ring width (TRW), earlywood BI (EWBI), latewood BI (LWBI) and delta BI (ΔBI) chronologies. The correlation analysis results indicated that BI chronologies are better than TRW chronology in relation to climate factors; EWBI chronology is a positive correlation with three temperatures (Tmean, Tmax and Tmin), whereas ΔBI and LWBI chronologies almost are negative correlations with temperatures. The LWBI chronology exhibited the highest correlation in July–August Tmin during 1955–2021 (r = −0.61, p < 0.01) and for the reconstruction. The reconstruction model could explain 36.64% of the observed variance. The reconstructed series spanned from 1843 to 2021 and documented three warm periods (1843–1863, 1874–1888 and 1992–2021) and one cold period (1911–1991), and Tmin rapidly warming since 1950s, which is similar to variation in the surrounding temperature reconstruction and is also consistent with the rate of global warming published by the IPCC. The result shows that the summer Tmin anomaly in southeast China is related significantly to the quasi‐biennial oscillation in the western Pacific and Indian Ocean. [ABSTRACT FROM AUTHOR]