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.  

Nitrogen losses from agriculture are already major sources of water and air pollution and greenhouse gas emissions and will grow as food production increases by 50% or more by 2050 even if farmers improve their management. This article suggests a technology-forcing, flexible regulatory strategy to encourage fertilizer manufactureers to increase the share and effectiveness of compounds that help limit nitrogen runoff. Such compounds, known as "enhanced efficiency fertilizers" have been shown on average to increase efficiency, reduce runoff and emissions, and increase yields but they have variable results and are not extensively used. This article suggests  incorporating an approached based on so-called "CAFE" standards, which have required automobile manuifacturers to increase the miles per gallon of the cars they sell over time. Requiring fertilizer manufacturers to sell more and better fertilizers over time could encourage the innovations necessary to truly alleviate nitrogen pollution.  Even without fertilizer innovations, the artgicle esetimates that applying this approach to the U.S. corn sector would save millions of dollars for farmers, generate billions in overall economic savings, and cause large reductions in nitrogen losses.  We suggest that governments such as those in China or California could enact these kinds of regulatory programs as part of their efforts to reduce greenhouse gas emissions and other forms of pollution.

The European Commission has agreed to a renewable energy directive (RED), which will require that all countries in the European Union increase the percentage of energy that comes from renewable energy by 2030. Although this general regulation is admirable, it treats nearly all bioenergy as fully qualifying, low-carbon, renewable bioenergy including the harvest of wood from forests deliberately to burn.

In January 2018, roughly 800 scientists wrote to the European Parliament warning them that doing so would likely lead to forms of bioenergy that actually increased carbon in the atmosphere for decades compared even to using fossil fuels. This letter along with a video about the issue and other materials can be found at www.empowerplants.com. The letter encouraged the Parliament to limit this qualifying renewable energy from forest biomass to residues and wastes, but the Parliament rejected such an amendment. Eventually, negotiations with the European Commission and Council of States led to an agreed RED that also allows cutting down and burning of whole trees. 

This article provides an academic treatment of this issue and finds that the RED could plausibly lead Europe to burn an additional amount of wood equal to all its present wood harvest and increase greenhouse gas emissions from energy use by 10% compared to the alternative. It discusses why the so-called sustainability criteria do not prevent this result. 

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.

For many years, governments and researchers have debated whether corn and wheat ethanol reduce greenhouse gas emissions when counting the emissions from land use change needed to replace the food, and the debates have relied on different global agriculture and land use models. Ultimately, the U.S. Environmental Protection Agency and the California Air Resources Board found that these ethanols did generate modestly fewer emissions than gasoline, relying on different models. The European Commission also commissioned a model that found lower emissions. Meanwhile, many supporters of biofuels argue that because all these models differ in their results, impacts on both greenhouse gases and food are too uncertain to reflect in policies.  

In this paper, we analyzed the model results carefully and found that they estimate lower emissions for ethanol because they estimate that from 20-50% of the calories in food are not replaced. Physically, the emissions result from reduced respiration of carbon dioxide (and wastes) by people and livestock. The models attribute these "savings" to the biofuels.  And if these estimates were wrong, the models would estimate higher greenhouse gas emissions.  The paper therefore highlights that much of the debate between models is which adverse effects predominate not whether these ethanols generate adverse effects.

Those without subscriptions to the journal can gain free access to the paper through these links.

Summary: http://www.sciencemag.org/cgi/content/summary/347/6229/1420?ijkey=3HDvP4VYvLiK2&keytype=ref&siteid=sci

Reprint: http://www.sciencemag.org/cgi/rapidpdf/347/6229/1420?ijkey=3HDvP4VYvLiK2&keytype=ref&siteid=sci

Full Text: http://www.sciencemag.org/cgi/content/full/347/6229/1420?ijkey=3HDvP4VYvLiK2&keytype=ref&siteid=sci