Jeffrey M Warren

Jeffrey M Warren

Plant Ecophysiologist


Jeff joined ORNL in 2010 and investigates ecosystem response to climate change within the Environmental Sciences Division and the Climate Change Science Institute. He holds an Adjunct Faculty appointment with the Department of Forestry, Wildlife and Fisheries at the University of Tennessee-Knoxville. His background includes physics (B.S. - Miami University), Forest Science (M.S. - NC State University) and Tree Physiology (Ph.D. - Washington State University. Warren’s research interests include how ecosystems are impacted by changes in the environment, including consequent interactions within and across species and how cascading effects are exhibited at higher trophic and scalar levels. His research investigates how terrestrial ecosystems adapt to changes in the environment, including subtle or severe abiotic or biotic disturbances. Much of his work is focused on plant physiology and soil-plant water relations, and how key mechanistic processes can be better represented in, and scaled to terrestrial biosphere models.


Stanley I. Auerbach Award Recipient for Excellence in Environmental Sciences (2014)

ORNL Significant Event Awards for contributions to multiple projects - FACE, SPRUCE, Root Function, NGEE-Tropics (2008-)

ORNL Laboratory Directed Research and Development Program funds awarded for six different research projects (2008-)

Dissertations Initiative for the Advancement of Climate Change Symposium I Scholar ​(DISCCRS) (2003)

EPA Science to Achieve Results Graduate Fellowship Recipient (1999)


(1) SPRUCE – black spruce bog ecosystem response to warming and elevated CO2:

(2) Extreme weather events, plant stress and ecosystem function

(3) Carbon partitioning in trees and soils

(4) Root functioning and representation in models

(5) Neutron imaging of soil-plant water flux

(6) NGEE-Tropics – tropical forest response to drought:


  1. Warren, JM, JR Brooks, FC Meinzer, JL Eberhart. 2008. Hydraulic redistribution of water from Pinus ponderosa trees to seedlings: evidence for an ectomycorrhizal pathway New Phytologist 178: 382–394.
  2. Domec, J-C, BL Lachenbruch, FC Meinzer, D Woodruff, JM Warren, KA McCulloh. 2008. Maximum height in a conifer is associated with conflicting requirements for xylem design. PNAS 105:12069-12074.
  3. De Kauwe, MG, BE Medlyn, S Zaehle, AP Walker, MC Dietze, T Hickler, AK Jain, Y Luo, WJ Parton, C Prentice, B Smith, PE Thornton, S Wang, Y-P Wang, D Wårlind, ES Weng, KY Crous, DS Ellsworth, PJ Hanson, H Seok-Kim, JM Warren, R Oren, RJ Norby. 2013. Forest water use and water use efficiency at elevated CO2: a model-data intercomparison at two contrasting temperate forest FACE sites. Global Change Biology 19:1759-79.
  4. Norby RJ, JM Warren, CM Iversen, BE Medlyn, RE McMurtrie. 2010. CO2 enhancement of forest productivity constrained by limited nitrogen availability. PNAS 107: 19368-19373.
  5. Warren, JM, E Pötzelsberger, SD Wullschleger, PE Thornton, H Hasenauer, RJ Norby. 2011. Ecohydrologic impact of reduced stomatal conductance in forests exposed to elevated CO2. Ecohydrology 4:196-210.
  6. Warren, JM, RJ Norby, SD Wullschleger. 2011. Elevated CO2 enhances premature leaf senescence during extreme climatic events in a temperate forest. Tree Physiology 31:117-130.
  7. Warren, JM, JR Brooks, MI Dragila, FC Meinzer. 2011. In situ separation of root hydraulic redistribution of soil water from liquid and vapor transport. Oecologia 166:899–911.
  8. Jensen, AM, JM Warren, PJ Hanson, J Childs, SD Wullschleger. 2015. Needle age and season influence photosynthetic temperature response in mature Picea mariana trees. Annals of Botany 116(5):821-832.  doi: 10.1093/aob/mcv115
  9. Warren, JM, PJ Hanson, CM Iversen, J Kumar, AP Walker, SD Wullschleger. 2015. Tansley Review - Incorporation of root structure and function in models – evaluation and recommendations. New Phytologist 205:59-78.
  10. Mao, J, DM Ricciuto, PE Thornton, JM Warren, AW King, X Shi, CM Iversen, RJ Norby. 2016. Evaluating the Community Land Model in a pine stand with shading manipulations and 13CO2 labeling. Biogeosciences 13:641-657. doi:10.5194/bg-13-641-2016
  11. Dhiman I, H Bilheux, K DeCarlo, SL Painter, L Santodonato, JM Warren. 2017. Quantifying root water extraction after drought recovery using sub-mm in situ empirical data. Plant and Soil

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