No Net Increase in Ecosystem Water Limitation Under Greenhouse Warming
5 affiliations
- 1Institute of Environment and Ecology Tsinghua Shenzhen International Graduate School Tsinghua University Shenzhen China
- 2Department of Earth and Planetary Sciences Harvard University Cambridge MA USA
- 3Department of Geography Université de Montréal Montreal QC Canada
- 4CAS Key Laboratory of Forest Ecology and Management Institute of Applied Ecology Chinese Academy of Sciences Shenyang China
- 5Department of Forestry and Natural Resources University of Kentucky Lexington KY USA
Abstract
Energy and water availability are essential controls on terrestrial ecosystem functions such as evapotranspiration. Accurately identifying the dominant regime of water or energy limitation on evapotranspiration is crucial for understanding ecosystem responses to climate change. Recent studies using Earth System Model (ESM) projections suggest widespread shifts from energy‐ to water‐limited conditions under global warming. We demonstrate that incorporating a thermodynamically appropriate energy indicator fundamentally changes this projection. Surface energy availability for evapotranspiration and related ecosystem functions is primarily determined by net radiation (Rn) rather than downwelling shortwave radiation or air temperature. Using this Rn‐based ecosystem limitation framework, we find no significant net increase in projected water limitation on either evapotranspiration or transpiration toward the end of the century. Idealized ESM CO2 experiments attribute this pattern to CO2‐induced physiological effects on vegetation—primarily stomatal regulation and enhanced water‐use efficiency—that largely dampen the increased water limitation from enhanced radiative forcing under greenhouse warming. Key physiological variables such as net primary production and leaf area index also show coherent and mechanistically interpretable responses to shifts in Rn‐based water–energy limitation regimes in transitional zones. These findings are consistent with patterns reported in other ecohydrologically based studies and are supported by empirical evidence of reduced vegetation sensitivity to dry conditions under elevated CO2. Our study bridges ecological and physical theories to improve ecosystem water‐energy limitation analysis and provides a clear mechanistic understanding of future ecosystem dynamics.
Related
- COVID-19 Emission Reductions Reveal the Efficiency and Warming Impact of Short-Lived Greenhouse Gases
- Recent increase in near-perpendicular tropical cyclone landfall fraction projected to emerge under high-emissions warming
- Replacing external inputs with ecosystem services to produce lamb meat can increase exposure to ecosystem disservices
- Diurnally asymmetric warming and hydroclimatic stress structure alpine ecosystem vulnerability in the Three-River headwaters region
- Warming and predation drive rapid evolution of ecosystem functioning but not functional traits
BibTeX
@article{xu2026increase,
title = {{No Net Increase in Ecosystem Water Limitation Under Greenhouse Warming}},
author = {Jiameng Xu and Kaighin A. McColl and Alexis Berg and Yu Liang and Jian Yang and Yuanchao Fan},
journal = {Earth's Future},
year = {2026},
month = oct,
doi = {10.1029/2026ef008222},
url = {https://doi.org/10.1029/2026ef008222},
note = {CC BY},
}
RIS
TY - JOUR
TI - No Net Increase in Ecosystem Water Limitation Under Greenhouse Warming
AU - Jiameng Xu
AU - Kaighin A. McColl
AU - Alexis Berg
AU - Yu Liang
AU - Jian Yang
AU - Yuanchao Fan
PY - 2026
DA - 2026/10/28
JO - Earth's Future
DO - 10.1029/2026ef008222
UR - https://doi.org/10.1029/2026ef008222
AB - Energy and water availability are essential controls on terrestrial ecosystem functions such as evapotranspiration. Accurately identifying the dominant regime of water or energy limitation on evapotranspiration is crucial for understanding ecosystem responses to climate change. Recent studies using Earth System Model (ESM) projections suggest widespread shifts from energy‐ to water‐limited conditions under global warming. We demonstrate that incorporating a thermodynamically appropriate energy indicator fundamentally changes this projection. Surface energy availability for evapotranspiration and related ecosystem functions is primarily determined by net radiation (Rn) rather than downwelling shortwave radiation or air temperature. Using this Rn‐based ecosystem limitation framework, we find no significant net increase in projected water limitation on either evapotranspiration or transpiration toward the end of the century. Idealized ESM CO2 experiments attribute this pattern to CO2‐induced physiological effects on vegetation—primarily stomatal regulation and enhanced water‐use efficiency—that largely dampen the increased water limitation from enhanced radiative forcing under greenhouse warming. Key physiological variables such as net primary production and leaf area index also show coherent and mechanistically interpretable responses to shifts in Rn‐based water–energy limitation regimes in transitional zones. These findings are consistent with patterns reported in other ecohydrologically based studies and are supported by empirical evidence of reduced vegetation sensitivity to dry conditions under elevated CO2. Our study bridges ecological and physical theories to improve ecosystem water‐energy limitation analysis and provides a clear mechanistic understanding of future ecosystem dynamics.
SN - 2328-4277
ER -