Gordon B Bonan
Biographic Data
| ID | 2544151 |
|---|---|
| NAME | Gordon B Bonan |
| GIVEN NAMES | Gordon B |
| FAMILY NAME | Bonan |
| SIGNATURE | BONAN G B |
| AFFILIATIONS | NSF National Center for Atmospheric Research |
| ORCID | 0000-0003-0830-6437 |
| VERIFIED | Yes |
| TOTAL WORKS | 14 |
| TOTAL CITATIONS | 2 |
| AUTHOR COUNT | 14 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 1990 |
| LATEST PUBLICATION YEAR | 2020 |
| H-INDEX | 1 |
The signature of internal variability in the terrestrial carbon cycle
Uncertainty in model initial states produces uncertainty in climate simulations because of unforced variability internal to the climate system. Climate scientists use initial-condition ensembles to separate the forced signal of climate change from the unforced internal variability. Our analysis of an 11-member initial-condition ensemble from the Community Earth System Model Version 2 that spans the period 1850–2014 shows that a similar ensemble a…
High predictability of terrestrial carbon fluxes from an initialized decadal prediction system
Interannual variations in the flux of carbon dioxide (CO 2 ) between the land surface and the atmosphere are the dominant component of interannual variations in the atmospheric CO 2 growth rate. Here, we investigate the potential to predict variations in these terrestrial carbon fluxes 1–10 years in advance using a novel set of retrospective decadal forecasts of an Earth system model. We demonstrate that globally-integrated net ecosystem producti…
Triose phosphate limitation in photosynthesis models reduces leaf photosynthesis and global terrestrial carbon storage
Triose phosphate utilization (TPU)-limited photosynthesis occurs when carbon export from the Calvin-Benson cycle cannot keep pace with carbon inputs and processing. This condition is poorly constrained by observations but may become an increasingly important driver of global carbon cycling under future climate scenarios. However, the consequences of including or omitting TPU limitation in models have seldom been quantified. Here, we assess the im…
Reducing uncertainty in projections of terrestrial carbon uptake
Carbon uptake by the oceans and terrestrial biosphere regulates atmospheric carbon dioxide concentration and affects Earth's climate, yet global carbon cycle projections over the next century are highly uncertain. Here, we quantify and isolate the sources of projection uncertainty in cumulative ocean and terrestrial carbon uptake over 2006-2100 by performing an analysis of variance on output from an ensemble of 12 Earth System Models. Whereas unc…
Effects of model structural uncertainty on carbon cycle projections: Biological nitrogen fixation as a case study
Uncertainties in terrestrial carbon (C) cycle projections increase uncertainty of potential climate feedbacks. Efforts to improve model performance often include increased representation of biogeochemical processes, such as coupled carbon–nitrogen (N) cycles. In doing so, models are becoming more complex, generating structural uncertainties in model form that reflect incomplete knowledge of how to represent underlying processes. Here, we explore …
Terrestrial Gross Carbon Dioxide Uptake: Global Distribution and Covariation with Climate
Carbon Cycle and Climate Change As climate change accelerates, it is important to know the likely impact of climate change on the carbon cycle (see the Perspective by Reich ). Gross primary production (GPP) is a measure of the amount of CO 2 removed from the atmosphere every year to fuel photosynthesis. Beer et al. (p. 834 , published online 5 July) used a combination of observation and calculation to estimate that the total GPP by terrestrial pl…
Recent decline in the global land evapotranspiration trend due to limited moisture supply
Parameterization of Urban Characteristics for Global Climate Modeling
To help understand potential effects of urbanization on climates of varying scales and effects of climate change on urban populations, urbanization must be included in global climate models (GCMs). To properly capture the spatial variability in urban areas, GCMs require global databases of urban extent and characteristics. This article describes methods and characteristics used to create a data set that can be utilized to simulate urban systems o…
Forests and Climate Change: Forcings, Feedbacks, and the Climate Benefits of Forests
The world's forests influence climate through physical, chemical, and biological processes that affect planetary energetics, the hydrologic cycle, and atmospheric composition. These complex and nonlinear forest-atmosphere interactions can dampen or amplify anthropogenic climate change. Tropical, temperate, and boreal reforestation and afforestation attenuate global warming through carbon sequestration. Biogeophysical feedbacks can enhance or dimi…
Protecting climate with forests
Policies for climate mitigation on land rarely acknowledge biophysical factors, such as reflectivity, evaporation, and surface roughness. Yet such factors can alter temperatures much more than carbon sequestration does, and often in a conflicting way. We outline a framework for examining biophysical factors in mitigation policies and provide some best-practice recommendations based on that framework. Tropical projects—avoided deforestation, fores…
Global Consequences of Land Use
Land use has generally been considered a local environmental issue, but it is becoming a force of global importance. Worldwide changes to forests, farmlands, waterways, and air are being driven by the need to provide food, fiber, water, and shelter to more than six billion people. Global croplands, pastures, plantations, and urban areas have expanded in recent decades, accompanied by large increases in energy, water, and fertilizer consumption, a…
Regions of Strong Coupling Between Soil Moisture and Precipitation
Previous estimates of land-atmosphere interaction (the impact of soil moisture on precipitation) have been limited by a lack of observational data and by the model dependence of computational estimates. To counter the second limitation, a dozen climate-modeling groups have recently performed the same highly controlled numerical experiment as part of a coordinated comparison project. This allows a multimodel estimation of the regions on Earth wher…
A Systems Analysis of the Global Boreal Forest
Using a Forest Stand Simulation Model to Examine the Ecological and Climatic Significance of the Late-Quaternary Pine-Spruce Pollen Zone in Eastern Virginia, U.S.A.
Full-glacial pollen records from southeastern United States are composed primarily of pine and spruce, with lesser amounts of fir, birch, and oak. A simulation model of forest dynamics was used to reconstruct the composition and structure of these forests on the Delmarva Peninsula of Virginia, where pollen data were available to test the model, and climate and soils data were available to drive the model. Reconstructed annual precipitation and su…
Using a Forest Stand Simulation Model to Examine the Ecological and Climatic Significance of the Late-Quaternary Pine-Spruce Pollen Zone in Eastern Virginia, U.S.A.
Full-glacial pollen records from southeastern United States are composed primarily of pine and spruce, with lesser amounts of fir, birch, and oak. A simulation model of forest dynamics was used to reconstruct the composition and structure of these forests on the Delmarva Peninsula of Virginia, where pollen data were available to test the model, and climate and soils data were available to drive the model. Reconstructed annual precipitation and su…
A Systems Analysis of the Global Boreal Forest
Regions of Strong Coupling Between Soil Moisture and Precipitation
Previous estimates of land-atmosphere interaction (the impact of soil moisture on precipitation) have been limited by a lack of observational data and by the model dependence of computational estimates. To counter the second limitation, a dozen climate-modeling groups have recently performed the same highly controlled numerical experiment as part of a coordinated comparison project. This allows a multimodel estimation of the regions on Earth wher…
Global Consequences of Land Use
Land use has generally been considered a local environmental issue, but it is becoming a force of global importance. Worldwide changes to forests, farmlands, waterways, and air are being driven by the need to provide food, fiber, water, and shelter to more than six billion people. Global croplands, pastures, plantations, and urban areas have expanded in recent decades, accompanied by large increases in energy, water, and fertilizer consumption, a…
Forests and Climate Change: Forcings, Feedbacks, and the Climate Benefits of Forests
The world's forests influence climate through physical, chemical, and biological processes that affect planetary energetics, the hydrologic cycle, and atmospheric composition. These complex and nonlinear forest-atmosphere interactions can dampen or amplify anthropogenic climate change. Tropical, temperate, and boreal reforestation and afforestation attenuate global warming through carbon sequestration. Biogeophysical feedbacks can enhance or dimi…
Protecting climate with forests
Policies for climate mitigation on land rarely acknowledge biophysical factors, such as reflectivity, evaporation, and surface roughness. Yet such factors can alter temperatures much more than carbon sequestration does, and often in a conflicting way. We outline a framework for examining biophysical factors in mitigation policies and provide some best-practice recommendations based on that framework. Tropical projects—avoided deforestation, fores…
Terrestrial Gross Carbon Dioxide Uptake: Global Distribution and Covariation with Climate
Carbon Cycle and Climate Change As climate change accelerates, it is important to know the likely impact of climate change on the carbon cycle (see the Perspective by Reich ). Gross primary production (GPP) is a measure of the amount of CO 2 removed from the atmosphere every year to fuel photosynthesis. Beer et al. (p. 834 , published online 5 July) used a combination of observation and calculation to estimate that the total GPP by terrestrial pl…
Recent decline in the global land evapotranspiration trend due to limited moisture supply
Parameterization of Urban Characteristics for Global Climate Modeling
To help understand potential effects of urbanization on climates of varying scales and effects of climate change on urban populations, urbanization must be included in global climate models (GCMs). To properly capture the spatial variability in urban areas, GCMs require global databases of urban extent and characteristics. This article describes methods and characteristics used to create a data set that can be utilized to simulate urban systems o…
Effects of model structural uncertainty on carbon cycle projections: Biological nitrogen fixation as a case study
Uncertainties in terrestrial carbon (C) cycle projections increase uncertainty of potential climate feedbacks. Efforts to improve model performance often include increased representation of biogeochemical processes, such as coupled carbon–nitrogen (N) cycles. In doing so, models are becoming more complex, generating structural uncertainties in model form that reflect incomplete knowledge of how to represent underlying processes. Here, we explore …
Reducing uncertainty in projections of terrestrial carbon uptake
Carbon uptake by the oceans and terrestrial biosphere regulates atmospheric carbon dioxide concentration and affects Earth's climate, yet global carbon cycle projections over the next century are highly uncertain. Here, we quantify and isolate the sources of projection uncertainty in cumulative ocean and terrestrial carbon uptake over 2006-2100 by performing an analysis of variance on output from an ensemble of 12 Earth System Models. Whereas unc…
Triose phosphate limitation in photosynthesis models reduces leaf photosynthesis and global terrestrial carbon storage
Triose phosphate utilization (TPU)-limited photosynthesis occurs when carbon export from the Calvin-Benson cycle cannot keep pace with carbon inputs and processing. This condition is poorly constrained by observations but may become an increasingly important driver of global carbon cycling under future climate scenarios. However, the consequences of including or omitting TPU limitation in models have seldom been quantified. Here, we assess the im…
High predictability of terrestrial carbon fluxes from an initialized decadal prediction system
Interannual variations in the flux of carbon dioxide (CO 2 ) between the land surface and the atmosphere are the dominant component of interannual variations in the atmospheric CO 2 growth rate. Here, we investigate the potential to predict variations in these terrestrial carbon fluxes 1–10 years in advance using a novel set of retrospective decadal forecasts of an Earth system model. We demonstrate that globally-integrated net ecosystem producti…
The signature of internal variability in the terrestrial carbon cycle
Uncertainty in model initial states produces uncertainty in climate simulations because of unforced variability internal to the climate system. Climate scientists use initial-condition ensembles to separate the forced signal of climate change from the unforced internal variability. Our analysis of an 11-member initial-condition ensemble from the Community Earth System Model Version 2 that spans the period 1850–2014 shows that a similar ensemble a…
Environmental Science (14 works) · Climate change (11 works) · Climatology (10 works) · Atmospheric sciences (9 works) · Ecosystem (8 works) · Geography (8 works) · Climate variability and models (7 works) · Computer Science (7 works) · Meteorology (7 works) · Atmospheric and Environmental Gas Dynamics (6 works)