Estimated carbon dioxide emissions from tropical deforestation improved by carbon-density maps

Journal name:
Nature Climate Change
Volume:
2,
Pages:
182–185
Year published:
DOI:
doi:10.1038/nclimate1354
Received
Accepted
Published online

Deforestation contributes 6–17% of global anthropogenic CO2 emissions to the atmosphere1. Large uncertainties in emission estimates arise from inadequate data on the carbon density of forests2 and the regional rates of deforestation. Consequently there is an urgent need for improved data sets that characterize the global distribution of aboveground biomass, especially in the tropics. Here we use multi-sensor satellite data to estimate aboveground live woody vegetation carbon density for pan-tropical ecosystems with unprecedented accuracy and spatial resolution. Results indicate that the total amount of carbon held in tropical woody vegetation is 228.7PgC, which is 21% higher than the amount reported in the Global Forest Resources Assessment 2010 (ref. 3). At the national level, Brazil and Indonesia contain 35% of the total carbon stored in tropical forests and produce the largest emissions from forest loss. Combining estimates of aboveground carbon stocks with regional deforestation rates4 we estimate the total net emission of carbon from tropical deforestation and land use to be 1.0PgCyr−1 over the period 2000–2010—based on the carbon bookkeeping model. These new data sets of aboveground carbon stocks will enable tropical nations to meet their emissions reporting requirements (that is, United Nations Framework Convention on Climate Change Tier 3) with greater accuracy.

At a glance

Figures

  1. Carbon contained in the aboveground live woody vegetation of tropical America, Africa and Asia (Australia excluded).
    Figure 1: Carbon contained in the aboveground live woody vegetation of tropical America, Africa and Asia (Australia excluded).

    The upper panels show the frequency distribution of carbon in units of MgCha−1 for each region. Inset figures across the bottom provide higher-resolution examples of the spatial detail present in the satellite-derived biomass data set. Carbon amount is represented in the maps as a colour scheme from dark brown (low carbon) to dark green (high carbon). See upper panels for numeric values.

  2. Comparison of national aboveground carbon stock estimates.
    Figure 2: Comparison of national aboveground carbon stock estimates.

    The figure shows five tropical nations for which FAO FRA 2005 (ref. 29), FAO FRA 2010 (ref. 3), FAO National Forest Monitoring and Assessment (NFMA) (ref. 17) and SDB estimates are available. Alternative carbon stock estimates30 are shown for comparison. The error bars indicate the uncertainity in national level estimates (at 95% CI for SDB data).

  3. Annual net emissions of carbon from land-use change in the tropics.
    Figure 3: Annual net emissions of carbon from land-use change in the tropics.

    The average carbon densities given by ref. 21, SDB, SDBdw and FRA 2010 (ref. 3) differ. An earlier estimate from ref. 22 is shown for comparison. The rates of deforestation given by refs 22 and 21 differ (the former is based on FRA 2005 (ref.  29) and the latter on FRA 2010 (ref. 3).

References

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Affiliations

  1. The Woods Hole Research Center, 149 Woods Hole Road, Falmouth, Massachusetts 02540, USA

    • A. Baccini,
    • S. J. Goetz,
    • W. S. Walker,
    • N. T. Laporte,
    • M. Sun,
    • J. Hackler,
    • P. S. A. Beck,
    • S. Samanta &
    • R. A. Houghton
  2. Boston University, Department of Geography and Environment, 675 Commonwealth Avenue, Boston, Massachusetts 02215, USA

    • D. Sulla-Menashe &
    • M. A. Friedl
  3. University of Maryland, 1149 Lefrak Hall, College Park, Maryland 20737, USA

    • R. Dubayah

Contributions

A.B., N.T.L., W.S.W., S.J.G. and R.A.H. designed the study. A.B., M.S., J.H. and D.S-M. conducted the analysis. A.B., R.D., S.S. and P.S.A.B. designed and conducted the error analysis. A.B., S.J.G., R.A.H., W.S.W. and M.A.F. wrote the paper.

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The authors declare no competing financial interests.

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