Last week, Project Drawdown released a major update to its landmark 2017 analysis of how the global community can implement currently available and readily scalable solutions to avoid the most catastrophic effects of climate change.

The update includes new models and data that have emerged over the last five years, incorporated into the solutions originally analyzed. Beyond that, 11 new solutions have been added, reflecting a growing understanding of the important role that oceans can and will need to play in mitigating climate change, of the critical need to target methane to reduce short-term warming pressure, and of the imperative to close the industrial loop in manufacturing with metals and plastics.

The update also reinforces Drawdown’s commitment to enabling ambitious climate action. The models now represent best available information around climate strategies that are financially viable and ready to be scaled immediately, and are a valuable resource for directing and measuring climate goals and targets. Drawdown is also demonstrating a commitment to transparency by releasing its research models to the public domain – those interested can find this ongoing work on Github.

Where does food waste land after the update? Food waste reduction remains the #1 solution under the scenario that limits end-of-century warming to 2°C. In the more ambitious scenario limiting warming to 1.5°C, projections for dramatic electrification and grid decarbonization put Onshore Wind and Utility-Scale Solar at #1 and #2 – Reducing Food Waste comes in at #4, just after Plant-Rich Diet. These two solutions provide far and away the most emissions reductions within the Food, Agriculture, and Land Use sector – and interestingly, are both demand-side solutions, highlighting the importance of integrating the consumer perspective in business and government implementation strategies.

When food goes uneaten, all the resources (energy, water, materials, money) that are required to produce, process, package, transport, store, and prepare it are wasted as well. This wasted food accounts for at least 8% of global greenhouse gas emissions (4% of U.S. annual emissions).

The Drawdown model for Reducing Food Waste projects future food demand for consumption, taking into account expected dietary changes.* Incremental adoption of reduced food waste was applied to all stages of the food supply chain, set to reach 50% reduction by 2050 for Scenario 1 and 75% reduction by 2050 for Scenario 2. Reduced food loss and waste is “diverted to feed current and future undernourished populations,” thereby reducing pressure on agricultural systems to meet growing demand. The major emissions reductions from reducing food waste come from avoiding the conversion of existing ecosystems to cropland and grassland, which is the main driver of the approximately 23% of global emissions that come from agriculture.

Strategic implementation of food waste reduction at a global scale will require a diverse range of solutions tailored to contextual causes. Drawdown notes that between regions, food is lost or wasted for different reasons and at different stages of the supply chain. In particular, regions of higher income generate more waste at the retail and consumer level, where each unit of food wasted has accumulated more embodied emissions moving through the supply chain. This means that “although solutions at the consumer level are difficult to implement and hard to measure, we must pursue them wherever consumer food waste is high…[and] we need to create incentives that change food waste behavior.”

Drawdown also calls for standardized measurement and tracking of food waste, and for reporting against food waste reduction targets that hold stakeholders accountable across sectors to corporate, supplier, and individual levels. The economic, social, and environmental costs are too great to delay progress any further – and the co-benefits of alleviating food insecurity, conserving water, saving money, protecting biodiversity, and more are too numerous and important to keep ignoring.

* This may contribute to Reduced Food Waste falling after Plant-Rich Diet in Scenario 2, since plant-rich diet is modeled first and the resulting future diets are pulled into the model for Reducing Food Waste. Meat-heavy diets make reduced food waste even more critical, since meat tends to be emissions-intensive.