Land Use

Peng, Liqing et al. “The Carbon Costs of Global Wood Harvests.” Nature (2023): n. pag.

After agriculture, wood harvest is the human activity that has most reduced the storage of carbon in vegetation and soils1,2. Although felled wood releases carbon to the atmosphere in various steps, the fact that growing trees absorb carbon has led to different carbon-accounting approaches for wood use, producing widely varying estimates of carbon costs. Many approaches give the impression of low, zero or even negative greenhouse gas emissions from wood harvests because, in different ways, they offset carbon losses from new harvests with carbon sequestration from growth of broad forest areas3,4. Attributing this sequestration to new harvests is inappropriate because this other forest growth would occur regardless of new harvests and typically results from agricultural abandonment, recovery from previous harvests and climate change itself. Nevertheless some papers count gross emissions annually, which assigns no value to the capacity of newly harvested forests to regrow and approach the carbon stocks of unharvested forests. Here we present results of a new model that uses time discounting to estimate the present and future carbon costs of global wood harvests under different scenarios. We find that forest harvests between 2010 and 2050 will probably have annualized carbon costs of 3.5–4.2 Gt CO2e yr−1, which approach common estimates of annual emissions from land-use change due to agricultural expansion. Our study suggests an underappreciated option to address climate change by reducing these costs.

Searchinger, Timothy et al. “EU Climate Plan Sacrifices Carbon Storage and Biodiversity for Bioenergy.” Nature 612 (2022): 27–30.
Zeng, Zhenzhong, and al. “Deforestation-Induced Warming over Tropical Mountain Regions Regulated by Elevation.” Nature Geoscience 14 (2021): 23–29.
Zeng, Zhenzhong et al. “ A Reversal in Global Terrestrial Stilling and Its Implications for Wind Energy Production .” Nature Climate Change 9 (2019): 979–985.
Searchinger, Tim et al. World Resources Report: Creating a Sustainable Food Future: A Menu of Solutions to Feed Nearly 10 Billion People by 2050. Washington, DC: World Resources Institute, 2019. Print.

The full, 566 page report, Creating a Sustainable Food Future:  A Menu of Solutions to Feed Nearly 10 Billion People by 2050 is now available. The report, of which I was lead author, explores how to meet food needs in 2050 while protecting ecosystems and reducing agricultural greenhouse gas emisisons to acceptable levels, and in ways that could help to reduce poverty and not exacerbate water challenges. The report was prepared by the World Resources Institute in collaboration with the World Bank, UN Environment, the UN Development Programme, and with technical contributions from INRA and CIRAD.

Some articles about the synthesis of the report appear in the New York Times, the Guardian, and Forbes.  

Searchinger, Timothy D. et al. “Assessing the Efficiency of Changes in Land Use for Mitigating Climate Change.” Nature 564 (2018): 249–253. Print.
When land shifts from producing corn to soybeans to kumquats, or from cropland to grazing land or bioenergy, or back to forest, does that help or hurt the world’s potential to mitigate climate change? This paper finds that typical methods used by policymakers and researchers to answer this question have not properly focused on the need to increase the efficiency of land to meet growing demands for both food and carbon storage. This limitation is particularly important because climate strategies require storing more carbon in forests and other native vegetation even as the world must produce 50 percent or more additional food per year. The paper provides a new method, called the Carbon Benefits Index, for making this evaluation, and includes a new spreadsheet tool that people can use to evaluate the climate conseuqneces of different changes in land use or production methods for specific hectares or parcels of land.  The World Resources Institute will keep that tool and its updates and will be available here. For a more thorough explanation of the new paper and its significance, please read this explanation.
Fetzel, T. et al. “Quantification of Uncertainties in Global Grazing Systems Assessment.” Global Biogeochemical Cycles 31.7 (2017): 1089–1102.
Searchinger, Timothy D., Tim Beringer, and Asa Strong. “Does the World Have Low-Carbon Bioenergy Potential from the Dedicated Use of Land?.” Energy Policy 110 (2017): 434–446.
Estes, L. D. et al. “ Reconciling Agriculture, Carbon and Biodiversity in a Savannah Transformation Frontier .” Philosophical Transactions of the Royal Society B 371.1703 (2016): n. pag.
Searchinger, Tim et al. The Great Balancing Act. Washington, DC: World Resources Institute, 2013. Print.
Searchinger, Tim D. The Food Forest and Carbon Challenge. Washington, DC: National Wildlife Federation, 2011. Print.
Searchinger, Timothy, and Ralph Heimlich. “Likely Impacts of Biofuel Expansion on Midwest Land and Water Resources.” International Journal of Biotechnology 11 (2009): 127–149.
Bustamente, Mercedes M.C. et al. “ Chapter 16: What Are the Final Land Limits? .” Biofuels: Environmental Consequences and Interactions With Changing Land Use. Ithaca, NY: Cornell University Library’s Initiatives in Publishing (CIP), 2009. 271–291. Print.
Searchinger, Timothy D., and Ralph E. Heimlich. “Estimating Greenhouse Gas Emissions from Soy-Based US Biodiesel When Factoring in Emissions from Land Use Change.” The Lifecycle Carbon Footprint of Biofuels 2008: 35–45.
Kline, Keith L. et al. “ Biofuels: Effects on Land and Fire .” Science 321.5886 (2008): 199–201.