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Title: Increasing atmospheric humidity and CO 2 concentration alleviate forest mortality risk

Climate-induced forest mortality is being increasingly observed throughout the globe. Alarmingly, it is expected to exacerbate under climate change due to shifting precipitation patterns and rising air temperature. However, the impact of concomitant changes in atmospheric humidity and CO 2 concentration through their influence on stomatal kinetics remains a subject of debate and inquiry. By using a dynamic soil–plant–atmosphere model, mortality risks associated with hydraulic failure and stomatal closure for 13 temperate and tropical forest biomes across the globe are analyzed. The mortality risk is evaluated in response to both individual and combined changes in precipitation amounts and their seasonal distribution, mean air temperature, specific humidity, and atmospheric CO 2 concentration. Model results show that the risk is predicted to significantly increase due to changes in precipitation and air temperature regime for the period 2050–2069. However, this increase may largely get alleviated by concurrent increases in atmospheric specific humidity and CO 2 concentration. The increase in mortality risk is expected to be higher for needleleaf forests than for broadleaf forests, as a result of disparity in hydraulic traits. These findings will further facilitate decisions about intervention and management of different forest types under changing climate.
ORCiD logo [1] ; ORCiD logo [2] ;  [1] ;  [3] ;  [4] ;  [5]
  1. Duke Univ., Durham, NC (United States). Nicholas School of the Environment
  2. Marquette Univ., Milwaukee, WI (United States). Dept. of Civil, Construction, and Environmental Engineering
  3. Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Biology
  4. Duke Univ., Durham, NC (United States). Nicholas School of the Environment and Dept. of Civil and Environmental Engineering
  5. Duke Univ., Durham, NC (United States). Dept. of Civil and Environmental Engineering
Publication Date:
Grant/Contract Number:
sc0011461; EAR-1454983; EAR-1331846; DGE-1068871; EAR-1316258; EAR-1338694; EAR-134470; DEB-1557176
Published Article
Journal Name:
Proceedings of the National Academy of Sciences of the United States of America
Additional Journal Information:
Journal Volume: 114; Journal Issue: 37; Journal ID: ISSN 0027-8424
National Academy of Sciences, Washington, DC (United States)
Research Org:
Duke Univ., Durham, NC (United States)
Sponsoring Org:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23). Climate and Environmental Sciences Division; National Aeronautic and Space Administration (NASA); National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States); World Climate Research Programme (WCRP); Univ. of Montana, Missoula, MT (United States); Max Planck Society, Jena (Germany). Max Planck Inst. for Biogeochemistry; National Science Foundation (NSF)
Country of Publication:
United States
54 ENVIRONMENTAL SCIENCES; forest mortality; drought; climate change; hydraulic failure; stomatal closure
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1425374