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• 1. [Article] Global vegetation monitoring: towards a sustainable technobiosphere

  The concept of sustainable resource management can be applied at multiple scales. Monitoring is an essential component of sustainable natural resource management schemes, and as we begin to confront the ...

  Citation × Citation Citation Abstract Copy Title: Global vegetation monitoring: towards a sustainable technobiosphere Author: Turner, David P. The concept of sustainable resource management can be applied at multiple scales. Monitoring is an essential component of sustainable natural resource management schemes, and as we begin to confront the need to manage natural resources at the global scale, the importance of monitoring at the global scale is also growing. The combination of satellite remote sensing, in situ measurements, and simulation modeling has the potential to deliver an annual assessment of status and trends for several measures of terrestrial biosphere structure and function relevant to sustainability. However, there is, as yet, no internationally coordinated effort in place to perform that analysis. Synthesis activity of that kind would support the development of global environmental governance institutions, including both nongovernmental organizations and international bodies. Title: Global vegetation monitoring: towards a sustainable technobiosphere Author: Turner, David P. The concept of sustainable resource management can be applied at multiple scales. Monitoring is an essential component of sustainable natural resource management schemes, and as we begin to confront the need to manage natural resources at the global scale, the importance of monitoring at the global scale is also growing. The combination of satellite remote sensing, in situ measurements, and simulation modeling has the potential to deliver an annual assessment of status and trends for several measures of terrestrial biosphere structure and function relevant to sustainability. However, there is, as yet, no internationally coordinated effort in place to perform that analysis. Synthesis activity of that kind would support the development of global environmental governance institutions, including both nongovernmental organizations and international bodies. Close

• 2. [Article] A large proportion of North American net ecosystem production is offset by emissions from harvested products, river/stream evasion, and biomass burning

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. The published article is copyrighted by Wiley-Blackwell and can be found at: http:...

  Citation × Citation Citation Abstract Copy Title: A large proportion of North American net ecosystem production is offset by emissions from harvested products, river/stream evasion, and biomass burning Author: Nemani, Ramakrishna, Wang, Weile L., Ritts, William D., Jacobson, Andrew R., Turner, David P. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. The published article is copyrighted by Wiley-Blackwell and can be found at: http://onlinelibrary.wiley.com/. Title: A large proportion of North American net ecosystem production is offset by emissions from harvested products, river/stream evasion, and biomass burning Author: Nemani, Ramakrishna, Wang, Weile L., Ritts, William D., Jacobson, Andrew R., Turner, David P. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. The published article is copyrighted by Wiley-Blackwell and can be found at: http://onlinelibrary.wiley.com/. Close

• 3. [Article] Reconciling estimates of the contemporary North American carbon balance among terrestrial biosphere models, atmospheric inversions, and a new approach for estimating net ecosystem exchange from inventory-based data

  The publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form ...

  Citation × Citation Citation Abstract Copy Title: Reconciling estimates of the contemporary North American carbon balance among terrestrial biosphere models, atmospheric inversions, and a new approach for estimating net ecosystem exchange from inventory-based data Author: de Jong, Bernardus, Heath, Linda S., Wei, Yaxing, Hayes, Daniel J., Stinson, Graham, Kurz, Werner A., Post, W. Mac, Jacobson, Andrew R., McGuire, A. David, West, Tristram O., Huntzinger, Deborah N., Turner, David P., Cook, Robert B., Birdsey, Richard A., Pan, Yude, McConkey, Brian G. The publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. Title: Reconciling estimates of the contemporary North American carbon balance among terrestrial biosphere models, atmospheric inversions, and a new approach for estimating net ecosystem exchange from inventory-based data Author: de Jong, Bernardus, Heath, Linda S., Wei, Yaxing, Hayes, Daniel J., Stinson, Graham, Kurz, Werner A., Post, W. Mac, Jacobson, Andrew R., McGuire, A. David, West, Tristram O., Huntzinger, Deborah N., Turner, David P., Cook, Robert B., Birdsey, Richard A., Pan, Yude, McConkey, Brian G. The publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. Close

• 4. [Article] Atmospheric inverse modeling to constrain regional-scale CO₂ budgets at high spatial and temporal resolution

  We present an inverse modeling framework designed to constrain CO2 budgets at regional scales. The approach captures atmospheric transport processes in high spatiotemporal resolution by coupling a mesoscale ...

  Citation × Citation Citation Abstract Copy Title: Atmospheric inverse modeling to constrain regional-scale CO₂ budgets at high spatial and temporal resolution Author: Law, Beverly E., Vickers, Dean, Michalak, Anna M., Turner, David P., Gockede, Mathias We present an inverse modeling framework designed to constrain CO2 budgets at regional scales. The approach captures atmospheric transport processes in high spatiotemporal resolution by coupling a mesoscale model with Lagrangian Stochastic backward trajectories. Terrestrial biosphere CO₂ emissions are generated through a simple diagnostic flux model that splits the net ecosystem exchange into its major components of gross primary productivity and autotrophic and heterotrophic respirations. The modeling framework assimilates state-of-the-art data sets for advected background CO₂ and anthropogenic fossil fuel emissions as well as highly resolved remote sensing products. We introduce a Bayesian inversion setup, optimizing a posteriori flux base rates for surface types that are defined through remote sensing information. This strategy significantly reduces the number of parameters to be optimized compared with solving fluxes for each individual grid cell, thus permitting description of the surface in a very high resolution. The model is tested using CO₂ concentrations measured in the fall and winter of 2006 at two AmeriFlux sites in Oregon. Because this database does not cover a full seasonal cycle, we focus on conducting model sensitivity tests rather than producing quantitative CO₂ flux estimates. Sensitivity tests on the influence of spatial and temporal resolution indicate that optimum results can be obtained using 4 h time steps and grid sizes of 6 km or less. Further tests demonstrate the importance of dividing biome types by ecoregions to capture their different biogeochemical responses to external forcings across climatic gradients. Detailed stand age information was shown to have a positive effect on model performance. Title: Atmospheric inverse modeling to constrain regional-scale CO₂ budgets at high spatial and temporal resolution Author: Law, Beverly E., Vickers, Dean, Michalak, Anna M., Turner, David P., Gockede, Mathias We present an inverse modeling framework designed to constrain CO2 budgets at regional scales. The approach captures atmospheric transport processes in high spatiotemporal resolution by coupling a mesoscale model with Lagrangian Stochastic backward trajectories. Terrestrial biosphere CO₂ emissions are generated through a simple diagnostic flux model that splits the net ecosystem exchange into its major components of gross primary productivity and autotrophic and heterotrophic respirations. The modeling framework assimilates state-of-the-art data sets for advected background CO₂ and anthropogenic fossil fuel emissions as well as highly resolved remote sensing products. We introduce a Bayesian inversion setup, optimizing a posteriori flux base rates for surface types that are defined through remote sensing information. This strategy significantly reduces the number of parameters to be optimized compared with solving fluxes for each individual grid cell, thus permitting description of the surface in a very high resolution. The model is tested using CO₂ concentrations measured in the fall and winter of 2006 at two AmeriFlux sites in Oregon. Because this database does not cover a full seasonal cycle, we focus on conducting model sensitivity tests rather than producing quantitative CO₂ flux estimates. Sensitivity tests on the influence of spatial and temporal resolution indicate that optimum results can be obtained using 4 h time steps and grid sizes of 6 km or less. Further tests demonstrate the importance of dividing biome types by ecoregions to capture their different biogeochemical responses to external forcings across climatic gradients. Detailed stand age information was shown to have a positive effect on model performance. Close