Free-Air Carbon Dioxide Enrichment (FACE) Experiments

Free-Air Carbon Dioxide Enrichment (FACE) Experiments

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Overview

From 1996 to 2007, the U.S. Department of Energy (DOE) supported large-scale experiments to study how ecosystems respond to changing atmospheric conditions. Through the Terrestrial Carbon Processes Program and the Program for Ecosystem Research, DOE funded two major types of trace gas enrichment experiments:

  • Free-Air Carbon Dioxide Enrichment (FACE) experiments
  • Open-Top Chamber (OTC) experiments

DOE’s Biological and Environmental Research (BER) program operated four FACE facilities in non-agricultural ecosystems distributed across the United States. Brookhaven National Laboratory provided central operations and coordination for several FACE sites. BER also supported OTC experiments in partnership with the Smithsonian Environmental Research Center in Maryland and Florida. A number of additional FACE and OTC studies were supported in whole or in part by BER. Many of these experiments evolved from individual studies into environmental research user facilities open to the broader scientific community.

Located at the Harshaw Experimental Forest near Rhinelander, Wisconsin, the Aspen FACE Experiment operated as a DOE User Facility, and was a collaborative effort among 11 organizations.

These projects were part of the CO₂ research network supported by the Global Change and Terrestrial Ecosystems, a core project of the International Geosphere Biosphere Programme (IGBP). Results from the experiments contributed to the Terrestrial Ecosystem Response to Atmospheric and Climatic Change initiative of the IGBP, a five-year effort that integrated experimental data and global change modeling. Together, these DOE-supported projects contributed to a global network of FACE experiments, connecting U.S. research efforts with international studies to better understand carbon, nutrient and water cycles across ecosystems.

This website has evolved as a central location to learn about some of these DOE supported experiments and link to datasets from those experiments.

See the 2020 Report

Distributed research facilities

Oak Ridge FACE

By studying how an entire forest stand functions as a system rather than isolated parts, the ORNL FACE experiment sought to understand how the eastern deciduous forest will be affected by CO2enrichment of the atmosphere. The project also sought to quantify the carbon feedback from the forest to the atmosphere.

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Features

  • Facility: Five 25-meter experiment plots built within a deciduous forest plantation on the Oak Ridge Environmental research park.
  • Forest Type: The stand was a sweetgum (Liquidambar styraciflua) monoculture planted in 1988, about 18 meters tall with a fully closed canopy.
  • Key Characteristics:
    • A closed canopy limited individual tree growth, creating realistic competition for light.
    • Full root occupancy constrained nutrient cycling, offering insights into long-term soil changes.
    • The larger size of mature trees compared to seedlings altered carbon cycling dynamics.
    • The extended time frame allowed scientists to measure gradual changes in soil carbon and ecosystem processes.
    • Data
    • The FACE data provided on this site are freely available and were furnished by individual FACE scientists who encourage their use. Please inform Rich Norby (Principal Investigator, ORNL FACE, [email protected]) of how you are using these data and of any publication plans.
    • Norby R J ; Iversen C M ; Warren J M ; Childs J ; Tharp M L (2010): Carbon and Nitrogen Stocks and Fluxes at ORNL FACE, Oak Ridge, Tennessee, 1998-2008. ORNL FACE Experiment, ESS-DIVE repository. Dataset. https://doi.org/10.15485/3020390
    • Annual carbon and nitrogen stocks and fluxes in wood, leaf, coarse root, and fine root fractions (1998-2008)
      • Biomass
      • Net Primary Production
      • Productivity
      • Carbon Mass
      • Nitrogen Mass
      • C:N Ratio
      • Nitrogen Uptake and Use Efficiency
      • Leaf Traits
      • PAR
      • Litter Mass
    • Riggs J ; Tharp M ; Norby R (2007): ORNL FACE Weather Data. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463817
    • Weather Data (1999-2010, gap-filled 1999-2008)
      • Air Temperature
      • PAR
      • Precipitation
      • Relative Humidity
      • Soil Temperature
      • Solar Irradiance
      • Wind Speed
    • Riggs J ; Tharp M ; Norby R (2007): ORNL FACE CO2 Concentration Data. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463842 
    • Carbon Dioxide Concentration Data (1999-2010, gap-filled 1999-2008)
      • Carbon Dioxide
      • Solar Angle
      • Wind Direction
      • Wind Speed
    • Norby R ; Tharp M (2007): ORNL FACE Leaf Area Index (LAI). CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463810   
    • Lead Area Index (1999-2009)
    • Norby R ; Tharp M (2007): ORNL FACE Basal Area. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463816 
    • Tree Basal Area (1997-2007)
    • Ledford J ; Norby R ; Tharp M (2007): ORNL FACE Fine Root Data. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463811 
    • Fine Root Data (1998-2007)
      • Root Mortality
      • Root Production
      • Root Standing Crop
    • Norby R ; Iverson C ; Tharp M (2007): ORNL FACE Nitrogen Concentrations (Leaves, Litter, Fine Roots, Wood). CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463845
    • Tree Nitrogen Concentrations (1998-2009)
      • Leaf Nitrogen
      • Litter Nitrogen
      • Fine Root Nitrogen
      • Wood Nitrogen
    • Finzi A C ; Norby R J ; Calfapietra C ; Gallet-Budynek A ; Gielen B ; Holmes W E ; Hoosbeek M R ; Iversen C M ; Jackson R B ; Kubiske M E ; Ledford J ; Liberloo M ; Oren R ; Polle A ; Pritchard S ; Zak D R ; Schlesinger W H ; Ceulemans R (2007): Nitrogen Stocks and Fluxes Across Four FACE Experiments, 1996-2004. ORNL FACE Experiment, ESS-DIVE repository. Dataset. https://doi.org/10.15485/3018019  
    • Nitrogen stocks and fluxes across wood, canopy, and fine root, leaf litter, and fine root mortality pools at ORNL FACE, Duke Forest FACE, Aspen FACE, and POP-EURO FACE sites (1996-2004)
      • Biomass
      • Net Primary Production
      • Productivity
      • Nitrogen Concentration
      • Nitrogen Mass
      • Nitrogen Uptake and Use Efficiency
      • Nitrogen Requirement, Retranslocation, and Return
    • Norby R (2021): ORNL FACE Tree Height, with data on height of a subset of trees measured every year, 1997-2009. Free-Air CO2 Enrichment (FACE) Experiment Synthesis Activities. ORNL FACE Experiment, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1798175
    • Tree Height (1997-2009)
    • Norby R ; Warren J ; Iversen C ; Childs J (2021): ORNL FACE Final Harvest, 2009, with data on leaf characteristics and tree mass. ORNL FACE Experiment, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1779883 
    • Tree Destructive Harvest Data (2009)
      • Basal Area
      • Height
      • Leaf Mass Area
      • Leaf Mass Volume
      • Leaf Thickness
      • Total Aboveground Wood Mass
      • Total Leaf Mass
    • Tharp M ; Norby R (2007): ORNL FACE Soil Moisture Data. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463846   
    • Soil Moisture (1997-2008)

Duke Forest FACE

The FACTS-I experiment helped researchers understand how forests store carbon, cycle nutrients, and interact with the atmosphere. Insights from this work are improving ecosystem and carbon cycle models, supporting more accurate predictions of how forests may function under future environmental conditions.

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Features

FACTS-I included eight FACE plots—four exposed to higher CO₂ concentrations and four that remain at natural levels as controls. The system began operation in 1994 with a prototype plot pair, followed by three additional plot pairs in 1996. The plots were sited in an unmanaged loblolly pine (Pinus taeda) plantation that had been established in 1983. 

In 1998, the prototype and its reference plot were divided by a soil barrier to enable combined CO₂ and soil nutrient enrichment experiments. This design was later expanded in 2005 to include all plot pairs, strengthening the dataset and enhancing the ability to study the effects of nitrogen in long-term forest responses to elevate CO2.

  • Comprehensive CO₂ Control: FACE technology allowed researchers to raise or maintain atmospheric CO₂ levels in open-air forest environments.
  • Integrated Soil Experiments: Soil barriers and nutrient additions made it possible to analyze how belowground processes interact with atmospheric changes.
  • Long-Term Data Collection: With operations spanning more than two decades, the facility provided rare, continuous measurements of forest carbon dynamics.
  • Scalable Design: The combination of elevated and ambient CO₂ plots allowed for comparisons across time, species, and treatment types.

Data

DUKE FACE data contained in the datasets below are freely available and were furnished by individual FACE scientists who encourage their use. Data can be accessed at the Environmental System Science Data Infrastructure for a Virtual Ecosystem (ESS-DIVE) by clicking the links below. Please inform Ram Oren (Principal Investigator, Duke Forest FACE) of how you are using these data and of any publication plans.

User note: Meteorological data files have 30-minute averaged or summed (as appropriate for the variable) data. Date and time stamps are recorded at the beginning of each line where: JDT is Julian day + decimal time. JD1 = Jan 1, 1990. 

Oren R ; Kim D ; Oishi A C ; Ward E (2022): Duke Forest FACE (FACTS-I): Meteorological and Soil Data. Duke Forest FACE – Forest-Atmosphere Carbon Transfer and Storage (FACTS-I), ESS-DIVE repository. Dataset. https://doi.org/10.15485/1895465.  

  • Meteorological Data (1997-2012)
    • Air Temperature
    • Net Radiation
    • Photosynthetically Active Radiation (PAR)
    • Precipitation
    • Relative Humidity
    • Saturated Vapor Pressure
    • Vapor Pressure Deficit
  • Soil Data (1997-2012)
    • Soil Moisture
    • Soil Water Potential
    • Soil Temperature

FACTS-I (2007): Duke FACE Micrometeorological Data. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463813. 

  • Meteorological Data (1997-2006)
    • Air Temperature
    • Net Radiation
    • Photosynthetically Active Radiation (PAR)
    • Precipitation
    • Relative Humidity
    • Saturated Vapor Pressure
    • Vapor Pressure Deficit

Oren R ; Kim D. (2007): Duke Forest FACE (FACTS-I): Early Meteorological Data, 1993-1996. Duke Forest FACE – Forest-Atmosphere Carbon Transfer and Storage (FACTS-I), ESS-DIVE repository. Dataset. https://doi.org/10.15485/3365732 

  • Meteorological Data (1993-1996)
    • Air Temperature
    • Precipitation
    • Relative Humidity
    • Saturated Vapor Pressure
    • Vapor Pressure Deficit 

Hendry G ; Lewin K ; Oren R ; Kim D (2008): Duke Forest FACE (FACTS-I): Carbon Dioxide (CO2) Concentration, 1993-2007. Duke Forest FACE – Forest-Atmosphere Carbon Transfer and Storage (FACTS-I), ESS-DIVE repository. Dataset. https://doi.org/10.15485/3365734 

  •  Carbon Dioxide (CO2) Concentration (1993-2007)

Oren R ; Kim D (2008): Duke Forest FACE (FACTS-I): Radiation and Wind Measurements, 1993-2007. Duke Forest FACE – Forest-Atmosphere Carbon Transfer and Storage (FACTS-I), ESS-DIVE repository. Dataset. https://doi.org/10.15485/3365737 

  • Cloud Cover
  • Photosynthetically Active Radiation (PAR)
  • Shortwave and Longwave Radiation
  • Solar Zenith Angle
  • Wind Speed and Direction

Finzi A C ; Norby R J ; Calfapietra C ; Gallet-Budynek A ; Gielen B ; Holmes W E ; Hoosbeek M R ; Iversen C M ; Jackson R B ; Kubiske M E ; Ledford J ; Liberloo M ; Oren R ; Polle A ; Pritchard S ; Zak D R ; Schlesinger W H ; Ceulemans R (2007): Nitrogen Stocks and Fluxes Across Four FACE Experiments, 1996-2004. ORNL FACE Experiment, ESS-DIVE repository. Dataset. https://doi.org/10.15485/3018019  

  • Nitrogen stocks and fluxes across wood, canopy, and fine root, leaf litter, and fine root mortality pools at ORNL FACE, Duke Forest FACE, Aspen FACE, and POP-EURO FACE sites (1996-2004)
    • Biomass
    • Net Primary Production
    • Productivity
    • Nitrogen Concentration
    • Nitrogen Mass
    • Nitrogen Uptake and Use Efficiency
    • Nitrogen Requirement, Retranslocation, and Return

Oren R ; Kim D ; Maier C ; Oishi A ; Ward E ; Kim H ; McCarthy H ; Medvigy D ; Palmroth S ; Pataki D ; Phillips N ; Schäfer K ; Tor-ngern P (2023): Duke Forest FACE (FACTS-I): Plant and Soil Response Data. Duke Forest FACE – Forest-Atmosphere Carbon Transfer and Storage (FACTS-I), ESS-DIVE repository. Dataset. https://doi.org/10.15485/2283434

  • Allometry (1996-2012)
  • Biomass (1996-2012)
  • Leaf-area index (1996-2012)
  • Net Primary Production (1996-2012)
  • Sap Flux (1998-2010)
  • Soil CO2 Flux (1996-2012)
  • Stem Temperature (2001-2012) 

FACTS-I (2007): Duke FACE Stem Temperature. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463821

  • Stem Temperature – raw and gap-filled (2004-2007)

FACTS-I (2007): Duke FACE Soil Temperature. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463808

  • Soil Temperature (1997-2004, Gap Filled: 2004-2006)

Nevada Desert FACE

Desert ecosystems may experience changes in productivity and water use under shifting CO₂ conditions. To better understand these dynamics, NDFF examined how carbon, nutrients, and water interact in an arid environment over time and seeks to answer several critical questions about the future of desert ecosystems.

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Features

The NDFF used Free-Air CO₂ Enrichment (FACE) technology to increase carbon dioxide levels in open-air environments without disrupting natural conditions.

At the NDFF site in the Mojave Desert, CO₂ concentrations are elevated by 50% above current atmospheric levels in three large experimental plots. Six additional plots remained at natural CO₂ levels to serve as controls.

This design allowed scientists to directly compare plant and ecosystem responses to different CO₂ levels and measure how carbon, nutrients, and water cycles are regulated in desert systems.

Data

The FACE data provided on this site are freely available and were furnished by individual FACE scientists who encourage their use. Data can be accessed at the Environmental System Science Data Infrastructure for a Virtual Ecosystem (ESS-DIVE) by clicking the links below.

Charlet D (2007): Nevada Desert Face Facility Micrometeorological Data. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463843 

  • Micrometeorological Data
    • Precipitation (1996-2006)
    • Wind speed (1997-2006)
    • Relative humidity (2001-2006)
    • Air temperature (1997- 2006)
    • PAR (2000-2006)
    • Solar radiation (1998- 2006)
    • CO2 concentration (1997-2006)
  • Operations
    • CO2 usage (1997-2005)
  • Plant Responses
    • Larrea tridentata shoot growth (1998-2002)
  • Soil characteristics
    • Soil particle size (1997)
    • Soil texture (1997)
    • Soil water potential (1997-2005)
  • Operations
    • CO2 usage (1997-2005)

Smith S ; Housman D (2007): Nevada Desert Face Facility Larrea tridentata Shoot Growth. CDIAC, ESS-DIVE repository. https://doi.org/10.15485/1463819  

  • Plant responses
    • Larrea tridentata shoot growth (1998-2007)
  • Micrometeorological Data
    • Precipitation (1996-2006)
    • Wind speed (1997-2006)
    • Relative humidity (2001-2006)
    • Air temperature (1997- 2006)
    • PAR (2000-2006)
    • Solar radiation (1998- 2006)
    • CO2 concentration (1997-2006)
  • Operations
    • CO2 usage (1997-2005)
  • Soil characteristics
    • Soil water potential (1997-2005)

Nowak R (2007): Nevada Desert Face Facility Soil Water Content (%Vol). CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463807 

  • Soil Particle Fractions (1997)
  • Soil Texture (1997)
  • Soil Water Content (1997-2005) 

Zitzer S (2007): Nevada Desert Face Facility Soil Texture and Particle Size. CDIAC, ESS-DIVE repository. Dataset. https://doi.org/10.15485/1463804 

  • Soil Particle Fractions (1997)
  • Soil Texture (1997)
  • Soil Water Content (1997-2005) 

Aspen FACE

By simulating various atmospheric conditions in a controlled, open-air environment, Aspen FACE helped scientists better understand how forests grow, store carbon, and interact with surrounding environments under elevated gas levels. Aspen FACE investigated critical questions about how forests process and store carbon, and how they respond to environmental stressors.

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Features

The Aspen FACE site included twelve 30-meter rings, each capable of controlling the concentrations of CO₂ and ozone in the air. This design allowed researchers to study the effects of each gas independently—and in combination—on a wide range of ecosystem characteristics, including:

  • Tree growth and development
  • Leaf and root structure
  • Soil carbon storage
  • Nutrient cycling and ecosystem function

Each ring was equipped with vertical ventpipes that release CO₂, ozone, or ambient air into the center of the plot. A computer-controlled feedback system continuously adjusted gas release every second to maintain consistent elevated levels.

Because the system operated in open air with no physical barriers, the forest’s natural conditions remained intact, aside from the controlled changes in gas concentrations.

Data

ORNL FACE data are freely available and were furnished by individual FACE scientists who encourage their use. Data can be accessed at the Environmental System Science Data Infrastructure for a Virtual Ecosystem (ESS-DIVE) or the Michigan Technological University’s Aspen FACE website by clicking the links below. 

Sober J ; Jones W ; Karnosky D. 2007. Aspen FACE CO2 Data. CDIAC, ESS-DIVE repository. https://doi.org/10.15485/1463818

  • Carbon Dioxide (1998-2008)
  • Soil C, N, d13C (1997-2008)
  • Soil Gas Exchange (1995-2005)
  • Soil Moisture (1999-2008)
  • Soil Texture (2009)

North Central Research Station. 2007. Aspen FACE Meteorological and Soil Data. CDIAC, ESS-DIVE repository. https://doi.org/10.15485/1463820

  • Meteorological Data (1998-2006)
    • Air temperature
    • Barometric Pressure
    • Relative Humidity
    • Net Radiation
    • Photosynthetically Active Radiation (PAR)
    • Precipitation
    • Wind Speed and Direction
  • Soil Temperature (1998-2006)
  • Soil Moisture (1998-2006) 

Finzi A C ; Norby R J ; Calfapietra C ; Gallet-Budynek A ; Gielen B ; Holmes W E ; Hoosbeek M R ; Iversen C M ; Jackson R B ; Kubiske M E ; Ledford J ; Liberloo M ; Oren R ; Polle A ; Pritchard S ; Zak D R ; Schlesinger W H ; Ceulemans R (2007): Nitrogen Stocks and Fluxes Across Four FACE Experiments, 1996-2004. ORNL FACE Experiment, ESS-DIVE repository. Dataset. https://doi.org/10.15485/3018019  

  • Nitrogen stocks and fluxes across wood, canopy, and fine root, leaf litter, and fine root mortality pools at ORNL FACE, Duke Forest FACE, Aspen FACE, and POP-EURO FACE sites (1996-2004)
    • Biomass
    • Net Primary Production
    • Productivity
    • Nitrogen Concentration
    • Nitrogen Mass
    • Nitrogen Uptake and Use Efficiency
    • Nitrogen Requirement, Retranslocation, and Return

View CO2 Data Summary (1998 – 2009)

View O3 Horly Data (1998 – 2009)

View O3 Data Summary (1998 – 2009)

Data archive and repository

The Environmental System Science Data Infrastructure for a Virtual Ecosystem (ESS-DIVE) serves as a central data repository and archive for DOE supported FACE and OTC data. Previously these data were archived by the Carbon Dioxide Information Analysis Center (CDIAC) and all of these datasets have been transferred to ESS-DIVE. These datasets can also be found on the DataONE platform.  

Archival of these valuable and unique data makes them more accessible to users worldwide and will facilitate cross-site synthesis research. The data ingest process involved QA/QC checks and data and metadata formatting for consistency with other FACE data and ESS-DIVE’s established best practices.

Navigate to the individual site pages above for more information and data access.

The Carbon Dioxide Information Analysis Center (CDIAC) served as the central data repository and archive for DOE-supported FACE and OTC research. The FACE Data Management System ensures that datasets are openly available and accessible to researchers worldwide, supporting cross-site data analysis and synthesis

FACE Model Data Synthesis (FACE-MDS)

The Free Air CO₂ Enrichment Model-Data Synthesis (FACE-MDS) project was created in 2008 with support from the National Center for Ecological Analysis and Synthesis. Since 2011, the FACE-MDS has been funded by the U.S. Department of Energy’s Office of Science through the Biological and Environmental Research program.

Illustration of FACE MDS Ecosystem

The FACE-MDS project’s initial goal was to benchmark terrestrial ecosystem model predictions of how ecosystems respond to elevated atmospheric CO2, using DOE FACE data from the ORNL and Duke experiments. As the project evolved, the focus shifted towards uncovering the underlying assumptions that shape model behavior, developing an approach called assumption-centered modeling[TR1] . We also expanded the sites in the analysis to include the Rhinelander FACE site, the Kennedy Space Center OTC experiment in a scrub-oak ecosystem, and the Prairie Heating and CO2 Enrichment (PHACE) experiment in a short-grass steppe ecosystem.   

FACE MDS Group Photo

Over the years, FACE-MDS has brought together scientists from over 35 institutions across the U.S. and internationally. The project is led by principal investigators at Oak Ridge National Laboratory in the United States, with key partners at the Hawkesbury Institute for the Environment in Australia, the Max Planck Institute for Biogeochemistry in Germany, and the University of Bristol in the UK.

Through a suite of influential papers and two international symposia, the FACE-MDS project has strengthened global understanding of how atmospheric CO₂ affects plants, ecosystems, and Earth systems. The project and team has identified areas where models can be improved, highlighted new questions for future research, and advanced new methods and approaches for comparing ecosystem models with experiment observations.

More details about the FACE-MDS project can be found in the 2020 DOE FACE Experiments report linked above. 

View FACE Data

Publications

2025

Hogan, J.A., Lichstein, J.W., Helmer, E.H., Craig, M.E., Fricke, E., Henrich, V., Kannenberg, S.A., Koven, C.D., Goldewjik, K.K., Lapola, D.M., Li, Y., Malhi, Y., Quinn, J., Roe, S., Terrer, C., Vilanova, E., Walker, A.P., Zhu, K., Ellis, E.C., 2025. Anthromes and forest carbon responses to global change. PLANTS, PEOPLE, PLANET 2025. https://doi.org/10.1002/ppp3.10609

Walker, A.P., Obermeier, W.A., Pongratz, J., Friedlingstein, P., Koven, C.D., Schwingshackl, C., Sitch, S., O’Sullivan, M., 2025. Harmonizing direct and indirect anthropogenic land carbon fluxes indicates a substantial missing sink in the global carbon budget since the early 20th century. PLANTS, PEOPLE, PLANET 2025. https://doi.org/10.1002/ppp3.10619

2024

Norby, R.J., Warren, J.M., Iversen, C.M., Walker, A.P., Childs, J., 2024. Getting allometry right at the Oak Ridge free-air CO2 enrichment experiment: Old problems and new opportunities for global change experiments. PLANTS, PEOPLE, PLANET 6, 1480–1489. https://doi.org/10.1002/ppp3.10565

Palmroth, S., Kim, D., Maier, C.A., Medvigy, D., Walker, A.P., Oren, R., 2024. Increased leaf area index and efficiency drive enhanced production under elevated atmospheric [CO2] in a pinedominated stand showing no progressive nitrogen limitation. Global Change Biology 30, e17190. https://doi.org/10.1111/gcb.17190

2022

Norby, R.J., Warren, J.M., Iversen, C.M., Childs, J., Jawdy, S.S., Walker, A.P., 2022. Forest stand and canopy development unaltered by 12 years of CO2 enrichment. Tree Physiology. 229, 2413–2445. doi:10.1093/treephys/tpab107.

Simmonds, M.B., Riley, W.J., Agarwal, D.A., Chen, X., Cholia, S., Crystal-Ornelas, R., Coon, E.T., Dwivedi, D., Hendrix, V.C., Huang, M., Jan, A., Kakalia, Z., Kumar, J., Koven, C.D., Li, L., Melara, M., Ramakrishnan, L., Ricciuto, D.M., Walker, A.P., Zhi, W., Zhu, Q., Varadharajan, C., 2022. Guidelines for Publicly Archiving Terrestrial Model Data to Enhance Usability, Intercomparison, and Synthesis. Data Science Journal 21, 3. https://doi.org/10.5334/dsj-2022-003

2021

Walker, A.P., De Kauwe, M.G., Bastos, A., Belmecheri, S., Georgiou, K., Keeling, R.F., McMahon, S.M., Medlyn, B.E., Moore, D.J.P., Norby, R.J., Zaehle, S., Anderson‐Teixeira, K.J., Battipaglia, G., Brienen, R.J.W., Cabugao, K.G., Cailleret, M., Campbell, E., Canadell, J.G., Ciais, P., Craig, M.E., Ellsworth, D.S., Farquhar, G.D., Fatichi, S., Fisher, J.B., Frank, D.C., Graven, H., Gu, L., Haverd, V., Heilman, K., Heimann, M., Hungate, B.A., Iversen, C.M., Joos, F., Jiang, M., Keenan, T.F., Knauer, J., Körner, C., Leshyk, V.O., Leuzinger, S., Liu, Y., MacBean, N., Malhi, Y., McVicar, T.R., Penuelas, J., Pongratz, J., Powell, A.S., Riutta, T., Sabot, M.E.B., Schleucher, J., Sitch, S., Smith, W.K., Sulman, B., Taylor, B., Terrer, C., Torn, M.S., Treseder, K.K., Trugman, A.T., Trumbore, S.E., Mantgem, P.J. van, Voelker, S.L., Whelan, M.E., Zuidema, P.A., 2021. Integrating the evidence
for a terrestrial carbon sink caused by increasing atmospheric CO2. New Phytologist 229, 2413–2445. doi:10.1111/nph.16866

2020

McDowell, N.G., Allen, C.D., Anderson-Teixeira, K., Aukema, B.H., Bond-Lamberty, B., Chini, L., Clark, J.S., Dietze, M., Grossiord, C., Hanbury-Brown, A., Hurtt, G.C., Jackson, R.B., Johnson, D.J., Kueppers, L., Lichstein, J.W., Ogle, K., Poulter, B., Pugh, T.A.M., Seidl, R., Turner, M.G., Uriarte, M., Walker, A.P., Xu, C., 2020. Pervasive shifts in forest dynamics in a changing world. Science 368. doi:10.1126/science.aaz9463

Wilcox, K.R., Komatsu, K.J., Avolio, M.L., 2020. Improving collaborations between empiricists and modelers to advance grassland community dynamics in ecosystem models. New Phytologist 228, 1467–1471. doi:10.1111/nph.16900

2019

Fleischer, K., Rammig, A., Kauwe, M.G.D., Walker, A.P., Domingues, T.F., Fuchslueger, L., Garcia, S., Goll, D.S., Grandis, A., Jiang, M., Haverd, V., Hofhansl, F., Holm, J.A., Kruijt, B., Leung, F., Medlyn, B.E., Mercado, L.M., Norby, R.J., Pak, B., Randow, C. von, Quesada, C.A., Schaap, K.J., Valverde-Barrantes, O.J., Wang, Y.-P., Yang, X., Zaehle, S., Zhu, Q., Lapola, D.M., 2019. Amazon forest response to CO2 fertilization dependent on plant phosphorus acquisition. Nature Geoscience doi:10.1038/s41561-019-0404-9


Jiang, M., Zaehle, S., Kauwe, M.G.D., Walker, A.P., Caldararu, S., Ellsworth, D.S., Medlyn, B.E., 2019. The quasi-equilibrium framework revisited: analyzing long-term CO2 enrichment responses in plant–soil models. Geoscientific Model Development 12, 2069–2089. doi:10.5194/gmd-12-2069-2019

Walker, A.P., Kauwe, M.G.D., Medlyn, B.E., Zaehle, S., Iversen, C.M., Asao, S., Guenet, B., Harper, A., Hickler, T., Hungate, B.A., Jain, A.K., Luo, Y., Lu, X., Lu, M., Luus, K., Megonigal, J.P., Oren, R., Ryan, E., Shu, S., Talhelm, A., Wang, Y.-P., Warren, J.M., Werner, C., Xia, J., Yang, B., Zak, D.R., Norby, R.J., 2019. Decadal biomass increment in early secondary succession woody ecosystems is increased by CO2 enrichment. Nature Communications 10, 454. doi:10.1038/s41467-019-08348-1

2017

Ryan, E.M., Ogle, K., Peltier, D., Walker, A.P., De Kauwe, M.G., Medlyn, B.E., Williams, D.G., Parton,W., Asao, S., Guenet, B., Harper, A.B., Lu, X., Luus, K.A., Zaehle, S., Shu, S., Werner, C., Xia, J., Pendall, E., 2017. Gross primary production responses to warming, elevated CO2, and irrigation:
quantifying the drivers of ecosystem physiology in a semiarid grassland. Global Change Biology 23, 3092–3106. doi:10.1111/gcb.13602

De Kauwe, M.G., Medlyn, B.E., Walker, A.P., Zaehle, S., Asao, S., Guenet, B., Harper, A.B., Hickler, T., Jain, A., Luo, Y., Lu, X., Luus, K., Parton, W.J., Shu, S., Wang, Y.-P., Werner, C., Xia, J., Pendall, E., Morgan, J.A., Ryan, E.M., Carrillo, Y., Dijkstra, F.A., Zelikova, T.J., Norby, R.J., 2017. Challenging terrestrial biosphere models with data from the long-term multi-factor
Prairie Heating and CO2 Enrichment experiment. Global Change Biology 23, 3623-3645. doi:10.1111/gcb.13643

Norby, R.J., Kauwe, M.G.D., Walker, A.P., Werner, C., Zaehle, S., Zak, D.R., 2017. Comment on “Mycorrhizal association as a primary control of the CO2 fertilization effect.” Science 355, 358–358. doi:10.1126/science.aai7976

2016

Medlyn, B.E., De Kauwe, M.G., Zaehle, S., Walker, A.P., Duursma, R.A., Luus, K., Mishurov, M., Pak, B., Smith, B., Wang, Y.-P., Yang, X., Crous, K.Y., Drake, J.E., Gimeno, T.E., Macdonald, C.A., Norby, R.J., Power, S.A., Tjoelker, M.G., Ellsworth, D.S., 2016. Using models to guide field experiments: a priori predictions for the CO2 response of a nutrient- and water-limited native Eucalypt woodland. Global Change Biology 22, 2834–2851. doi:10.1111/gcb.13268

Norby, R.J., De Kauwe, M.G., Domingues, T.F., Duursma, R.A., Ellsworth, D.S., Goll, D.S., Lapola, D.M., Luus, K.A., MacKenzie, A.R., Medlyn, B.E., Pavlick, R., Rammig, A., Smith, B., Thomas, R., Thonicke, K., Walker, A.P., Yang, X., Zaehle, S., 2016. Model-data synthesis for the next generation of forest free-air CO2 enrichment (FACE) experiments. New Phytologist 209, 17–28. doi:10.1111/nph.13593

2015

Medlyn, B.E., Zaehle, S., De Kauwe, M.G., Walker, A.P., Dietze, M.C., Hanson, P.J., Hickler, T., Jain, A.K., Luo, Y., Parton, W.J., Prentice, I.C., Thornton, P.E., Wang, S., Wang, Y.-P., Weng, E., Iversen, C.M., McCarthy, H.R., Warren, J.M., Oren, R., Norby, R.J., 2015. Using ecosystem experiments to improve vegetation models Nature Climate Change 5, 528–534. doi:10.1038/nclimate2621. [pdf]

Walker, A.P., Zaehle, S., Medlyn, B.E., De Kauwe, M.G., Asao, S., Hickler, T., Parton, W., Ricciuto, D., Wang, Y.-P., Wårlind, D., Norby, R.J., 2015. Predicting long-term carbon sequestration in response to CO2 enrichment: How and why do current ecosystem models differ? Global Biogeochemical Cycles 2014GB004995. doi:10.1002/2014GB004995 [pdf]

2014

De Kauwe, M.G., Medlyn, B.E., Zaehle, S., Walker, A.P., Dietze, M.C., Wang, Y.-P., Luo, Y., Jain, A.K., El-Masri, B., Hickler, T., Wårlind, D., Weng, E., Parton, W.J., Thornton, P.E., Wang, S., Prentice, I.C., Asao, S., Smith, B., McCarthy, H.R., Iversen, C.M., Hanson, P.J., Warren, J.M., Oren, R., Norby,
R.J., 2014. Where does the carbon go? A model–data intercomparison of vegetation carbon allocation and turnover processes at two temperate forest free-air CO2 enrichment sites. New Phytologist 203, 883–899. doi:10.1111/nph.12847

Walker, A.P., Hanson, P.J., De Kauwe, M.G., Medlyn, B.E., Zaehle, S., Asao, S., Dietze, M., Hickler, T., Huntingford, C., Iversen, C.M., Jain, A., Lomas, M., Luo, Y., Mccarthy, H., Parton, W.J., Prentice, I.C., Thornton, P.E., Wang, S., Wang, Y.-P., Wårlind, D., Weng, E., Warren, J.M., Woodward, F.I., Oren, R., Norby, R.J., 2014. Comprehensive ecosystem model-data synthesis using multiple data sets at two temperate forest free-air CO2 enrichment experiments: Model performance at ambient CO2 concentration. Journal of Geophysical Research Biogeosciences 119, 2013JG002553. doi:10.1002/2013JG002553

Zaehle, S., Medlyn, B.E., De Kauwe, M.G., Walker, A.P., Dietze, M.C., Hickler, T., Luo, Y., Wang, Y.-P., El-Masri, B., Thornton, P., Jain, A., Wang, S., Wårlind, D., Weng, E., Parton, W., Iversen, C.M., Gallet-Budynek, A., Mccarthy, H., Finzi, A., Hanson, P.J., Prentice, I.C., Oren, R., Norby, R.J., 2014. Evaluation of 11 terrestrial carbon–nitrogen cycle models against observations from two temperate Free-Air CO2 Enrichment studies. New Phytologist 202, 803–822. doi:10.1111/nph.12697

Contact

Anthony Walker

Research Staff

[email protected]