Abstract
Previous studies have examined land use change as a driver of global change, but the translation of land use change into land cover conversion has been largely unconstrained. Here we quantify the effects of land cover conversion uncertainty on the global carbon and climate system using the integrated Earth System Model. Our experiments use identical land use change data and vary land cover conversions to quantify associated uncertainty in carbon and climate estimates. Land cover conversion uncertainty is large, constitutes a 5 ppmv range in estimated atmospheric CO2 in 2004, and generates carbon uncertainty that is equivalent to 80% of the net effects of CO2 and climate and 124% of the effects of nitrogen deposition during 1850–2004. Additionally, land cover uncertainty generates differences in local surface temperature of over 1°C. We conclude that future studies addressing land use, carbon, and climate need to constrain and reduce land cover conversion uncertainties.
| Original language | English |
|---|---|
| Pages (from-to) | 974-982 |
| Number of pages | 9 |
| Journal | Geophysical Research Letters |
| Volume | 45 |
| Issue number | 2 |
| DOIs | |
| State | Published - Jan 28 2018 |
Funding
This work is supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research under award DE-AC02-05CH11231 as part of the Integrated Assessment Research and Earth System Modeling Programs and with additional support from the Accelerated Climate Modeling for Energy project. J. Mao and X. Shi are also partially supported by the Reducing Uncertainties in Biogeochemical Interactions through Synthesis and Computing Scientific Focus Area (RUBISCO SFA), which is sponsored by the Regional and Global Climate Modeling (RGCM) Program in the Climate and Environmental Sciences Division (CESD) of the Biological and Environmental Research (BER) Program in the U.S. Department of Energy Office of Science. G. Hurtt and L. Chini gratefully acknowledge the support of NASA-IDS and DOE-SciDAC programs. Oak Ridge National Laboratory is managed by UT-BATTELLE for DOE under contract DE-AC05-00OR22725. Project used resources of the National Energy Research Scientific Computing Center (NERSC), which is a DOE Office of Science user Facility. The CESM project is supported by the National Science Foundation and the Office of Science (Biological and Environmental Research) of the U.S. Department of Energy. The authors also acknowledge high-performance computing support from Yellowstone (ark:/85065/ d7wd3xhc) provided by NCAR’s Computational and Information Systems Laboratory, sponsored by the National Science Foundation. The authors are grateful to Ben Bond-Lamberty and reviewers for providing insightful feedback on drafts of this manuscript. The authors declare that there are no real or perceived financial conflicts of interest. Model outputs corresponding with the figures are included as supporting information, and the raw model outputs will be archived for at least 5 years from publication. Please contact the corresponding author to obtain access to the raw model outputs. The iESM code is available at https://github.com/ACME-Climate/iESM. On the Yellowstone supercomputing cluster, the eight land-only simulations used about 224,000 processor hours each, and two of the fully coupled simulations used about 700,000 processor hours each. The other two fully coupled simulations used about 1.5 M processor hours each on the Edison supercomputing cluster at NERSC and were charged twice this amount due to a 2 times charge factor.
Keywords
- Earth system
- carbon
- climate
- land cover
- land use
- uncertainty