Summer soil drying exacerbated by earlier spring greening of northern vegetation

Earlier vegetation greening under climate change raises evapotranspiration and thus lowers spring soil moisture, yet the extent and magnitude of this water deficit persistence into the following summer remain elusive. We provide observational evidence that increased foliage cover over the Northern Hemisphere, during 1982-2011, triggers an additional soil moisture deficit that is further carried over into summer. Climate model simulations independently support this and attribute the driving process to be larger increases in evapotranspiration than in precipitation. This extra soil drying is projected to amplify the frequency and intensity of summer heatwaves. Most feedbacks operate locally, except for a notable…

• SR
  Sight Research UK

  Awards: NE/I006702/1, NE/F005997/1
• NN
  National Natural Science Foundation of China

  Awards: 2019QZKK0208, 41530528, 41561134016, 41988101, B14001
• CN
  Centre National de la Recherche Scientifique
• HE
  Higher Education Discipline Innovation Project

  Award: B14001
• NE
  Natural Environment Research Council

  Awards: NE/I006702/1, NE/F005997/1
• NK
  National Key Research and Development Program of China

  Awards: 41988101, 2019QZKK0208, 2018YFC1507704
• NK
  National Key Research and Development Program of China Stem Cell and Translational Research

  Award: Grant-2018YFC1507704