Login / Signup

Recent global decline in rainfall interception loss due to altered rainfall regimes.

Xu LianWenli ZhaoPierre Gentine
Published in: Nature communications (2022)
Evaporative loss of interception (E i ) is the first process occurring during rainfall, yet its role in large-scale surface water balance has been largely underexplored. Here we show that E i can be inferred from flux tower evapotranspiration measurements using physics-informed hybrid machine learning models built under wet versus dry conditions. Forced by satellite and reanalysis data, this framework provides an observationally constrained estimate of E i , which is on average 84.1 ± 1.8 mm per year and accounts for 8.6 ± 0.2% of total rainfall globally during 2000-2020. Rainfall frequency regulates long-term average E i changes, and rainfall intensity, rather than vegetation attributes, determines the fraction of E i in gross precipitation (E i /P). Rain events have become less frequent and more intense since 2000, driving a global decline in E i (and E i /P) by 4.9% (6.7%). This suggests that ongoing rainfall changes favor a partitioning towards more soil moisture and runoff, benefiting ecosystem functions but simultaneously increasing flood risks.
Keyphrases
  • machine learning
  • big data
  • artificial intelligence
  • deep learning