Reducing Uncertainty in Biogeochemical Interactions through Synthesis and Computation (RUBISCO) Scientific Focus Area (SFA)

As earth system models (ESMs) become increasingly complex, there is a growing need for comprehensive and multifaceted evaluation, analysis, and diagnosis of model results. The relevance of model predictions to the U.S. Department of Energy’s (DOE’s) mission hinges in part on the assessment of quantitative error bounds and levels of uncertainty, requiring repeatable, automated analysis methods and new observational and experimental data to constrain model results.

This scientific focus area (SFA) has pioneered the development and application of new hypothesis-driven diagnostic approaches for evaluating ESM representations of biogeochemical and hydrological processes at site, regional, and global scales; released two open source model benchmarking software packages; and provided international leadership for global biogeochemical and hydrological model benchmarking. The overarching goals of the SFA are to identify and quantify interactions between biogeochemical and hydrological cycles and the earth system, and to quantify and reduce uncertainties in ESMs associated with those interactions.

The SFA will:

1) develop hypothesis-driven approaches for evaluation of ESM biogeochemical and physical process representations at site, regional, and global scales;

2) investigate the degree to which contemporary observations can be used to reduce uncertainties in future scenarios, including use of an “emergent constraint” approach;

3) leverage the growing collection of laboratory, field, and remote sensing data sets for systematic evaluation of ESM biogeochemical processes;

4) conduct intercomparison experiments using DOE’s Energy Exascale Earth System Model (E3SM) framework; and

5) evaluate the performance of biogeochemical and hydrological process representations in ESMs and their interactive effects on the earth system.

Project Term: 
2017 to 2020
Project Type: 
Laboratory Funded Research

Research Highlights:

A Functional Response Metric for the Temperature Sensitivity of Tropical Ecosystems Highlight Presentation
Biases in Forest Distributions in CMIP5 Models Lead to Large Uncertainties in Extratropical Forest Biomass Highlight Presentation
Contribution of Environmental Forcings to US Runoff Changes for the Period 1950–2010 Highlight Presentation
Forest Response to Rising CO2 Drives Zonally Asymmetric Rainfall Change Over Tropical Land Highlight Presentation
Greening of the Land Surface in the World’s Cold Regions Consistent with Recent Warming Highlight Presentation
Merging a mechanistic enzymatic model of soil heterotrophic respiration into an ecosystem model in two AmeriFlux sites of northeastern USA. Highlight Presentation
Model-based analysis of the impact of diffuse radiation on CO2 exchange in a temperate deciduous forest. Highlight Presentation
Observed and CMIP5-Simulated Sensitivities of Spring Greenup to Preseason Climate Highlight
Reversal of Increasing Tropical Ocean Hypoxia Trends with Sustained Climate Warming Highlight Presentation
Strong Dependence of Simulated Carbon-Nitrogen Dynamics on Numerical Coupling Between Nitrogen Uptake and Mineralization Processes Highlight Presentation
Sustained Climate Warming Drives Declining Marine Biological Productivity Highlight Presentation
Synthetic Ozone Deposition and Stomatal Uptake at Flux Tower Sites Highlight Presentation
The Terrestrial Carbon Sink Highlight Presentation