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Plant phenology is a sensitive indicator of climate change1,2,3,4 and plays an important role in regulating carbon uptake by plants5,6,7. Previous studies have focused on spring leaf-out by
daytime temperature and the onset of snow-melt time8,9, but the drivers controlling leaf senescence date (LSD) in autumn remain largely unknown10,11,12. Using long-term ground phenological
records (14,536 time series since the 1900s) and satellite greenness observations dating back to the 1980s, we show that rising pre-season maximum daytime (Tday) and minimum night-time
(Tnight) temperatures had contrasting effects on the timing of autumn LSD in the Northern Hemisphere (> 20° N). If higher Tday leads to an earlier or later LSD, an increase in Tnight
systematically drives LSD to occur oppositely. Contrasting impacts of daytime and night-time warming on drought stress may be the underlying mechanism. Our LSD model considering these
opposite effects improved autumn phenology modelling and predicted an overall earlier autumn LSD by the end of this century compared with traditional projections. These results challenge the
notion of prolonged growth under higher autumn temperatures, suggesting instead that leaf senescence in the Northern Hemisphere will begin earlier than currently expected, causing a
positive climate feedback.
The data that support the findings of this study are available from the corresponding author upon request.
In the version of this Letter originally published, there were errors in Fig. 1a. The sites denoted purple were described in the legend as ‘Pday>0.05 & Pnight>0.05’, but should have been
labelled ‘Pday0.05’. The sites denoted green were described in the legend as ‘Pday>0.05 & Pnight>0.05’, but should have been labelled ‘Pday>0.05 & Pnight0.05 & Pnight>0.05’, but should have
been labelled ‘Pday