Timothy B. Sulser

Food security, farming, and climate change to 2050: Scenarios, results, policy options

As the global population grows and incomes in poor countries rise, so too, will the demand for food, placing additional pressure on sustainable food production. Climate change adds a further challenge, as changes in temperature and precipitation threaten agricultural productivity and the capacity to feed the worlds population. This study assesses how serious the danger to food security might be and suggests some steps policymakers can take to remedy the situation.

The impact of organic farming on food security in a regional and global perspective

The spread of organic and agro-ecological farming (OF) methods in developing countries has raised a debate whether a large scale adoption of OF will increase or decrease global food security. This will however depend on a number of socio-economic factors together with the relative yield levels of OF versus conventional farming systems. Relative yields again depend on a number of agro ecological factors and the characteristics of farming systems before conversion. In areas with intensive high-input agriculture, conversion to OF will most often lead to a reduction in crop yields per ha by 20-45 % in crop rotations integrated with leguminous forage crops. In many areas with low input agricultural systems farmers have little incentive or access to use chemical fertiliser and pesticides, and yields may increase when agro ecological principles are introduced. While present food production in theory is sufficient to cover the energy and protein needs of the global population there are still more than 740 million food insecure people, the majority of whom live in South Asia and Africa South of Sahara (SSA). This number will only decrease over the next 20 years if the present policies are changed. The food policy model IMPACT was used to project possible effects on food security of a large scale conversion to OF in Europe/North America (E/NA) and SSA. Results indicate that a conversion of approximately 50 % of E/NA agricultural area will have a 6-10 % impact on world prices on (non-meat) agricultural commodities under the assumptions of 35 % lower OF yields after conversion and 50 % higher yield growth rates compared with conventional crop yields. The indirect effect on food security in SSA would be very small up scaling experiences from case studies into scenarios for conversion of 50 % of agricultural area in SSA results in increased self-sufficiency and decreased net food import to the region. Given the assumption of higher relative yields in most organic crops compared with existing low input agriculture, there is potential for improving local food security in SSA if non-certified OF is supported by capacity building and research. More knowledge is needed, however, to confirm that these optimistic results of non-certified OF apply to large areas in SSA and other regions with low input agriculture.

Climate change impacts and adaptation options for water and food in Pakistan: scenario analysis using an integrated global water and food projections model

Climate change is expected to considerably affect the water resources in the Indus River basin in Pakistan and thus agricultural production in the country. This article reports an analysis of the impacts of various climate scenarios on both water resources and food production out to 2050. While changes in water availability range from –12% to +24%, depending on the scenario, crop yield and production impacts are negative across all scenarios, and net food imports increase. We suggest a combination of accelerated investment in agricultural research and increased water-use efficiency in agriculture to reduce the adverse impacts of climate change on water and food.

The future role of agriculture in the Arab region’s food security

The 2007–2008 food crisis and subsequent economic recession have severely undermined food security and agricultural sustainability worldwide. Failures in market functioning and trade openness have posed particularly high risks to the import-dependent countries in the Arab region. Many of the global causes of the price spikes are still in place, creating uncertainty about food availability and access in the future. Especially in the Arab region, these uncertainties are compounded by water scarcity. A long-term outlook is essential for formulating appropriate policy and investment strategies in order to ensure future food security for the region. After a brief discussion of trends in agricultural growth and investment, this paper presents projections by the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT) on agriculture production, trade, demand, prices, and food security up to 2025 and 2050. Simulations are used to compare a baseline scenario (with climate change) with two scenarios incorporating increased investment and supportive policies. The results highlight the key role of agricultural research, as well as expanded irrigation, improved natural resource management, and enhanced market efficiency, in improving food security. Four priority areas are proposed: investments in agricultural research and development, rural infrastructure, and rural institutions; more open regional and international trade to facilitate commodity flows and alleviate supply shortages; pro-poor food and nutrition interventions; and cross-cutting issues of policy coherence, gender dimensions, inclusion of traditional populations, and coordination mechanisms to deal with climate change and ecosystem challenges.

Health and nutritional aspects of sustainable diet strategies and their association with environmental impacts: a global modelling analysis with country-level detail

Summary Background Sustainable diets are intended to address the increasing health and environmental concerns related to food production and consumption. Although many candidates for sustainable diets have emerged, a consistent and joint environmental and health analysis of these diets has not been done at a regional level. Using an integrated health and environmental modelling framework for more than 150 countries, we examined three different approaches to sustainable diets motivated by environmental, food security, and public health objectives. Methods In this global modelling analysis, we combined analyses of nutrient levels, diet-related and weight-related chronic disease mortality, and environmental impacts for more than 150 countries in three sets of diet scenarios. The first set, based on environmental objectives, replaced 25–100% of animal-source foods with plant-based foods. The second set, based on food security objectives, reduced levels of underweight, overweight, and obesity by 25–100%. The third set, based on public health objectives, consisted of four energy-balanced dietary patterns: flexitarian, pescatarian, vegetarian, and vegan. In the nutrient analysis, we calculated nutrient intake and changes in adequacy based on international recommendations and a global dataset of nutrient content and supply. In the health analysis, we estimated changes in mortality using a comparative risk assessment with nine diet and weight-related risk factors. In the environmental analysis, we combined country-specific and food group-specific footprints for greenhouse gas emissions, cropland use, freshwater use, nitrogen application, and phosphorus application to analyse the relationship between the health and environmental impacts of dietary change. Findings Following environmental objectives by replacing animal-source foods with plant-based ones was particularly effective in high-income countries for improving nutrient levels, lowering premature mortality (reduction of up to 12% [95% CI 10–13] with complete replacement), and reducing some environmental impacts, in particular greenhouse gas emissions (reductions of up to 84%). However, it also increased freshwater use (increases of up to 16%) and had little effectiveness in countries with low or moderate consumption of animal-source foods. Following food-security objectives by reducing underweight and overweight led to similar reductions in premature mortality (reduction of up to 10% [95% CI 9–11]), and moderately improved nutrient levels. However, it led to only small reductions in environmental impacts at the global level (all impacts changed by <15%), with reduced impacts in high-income and middle-income countries, and increased resource use in low-income countries. Following public health objectives by adopting energy-balanced, low-meat dietary patterns that are in line with available evidence on healthy eating led to an adequate nutrient supply for most nutrients, and large reductions in premature mortality (reduction of 19% [95% CI 18–20] for the flexitarian diet to 22% [18–24] for the vegan diet). It also markedly reduced environmental impacts globally (reducing greenhouse gas emissions by 54–87%, nitrogen application by 23–25%, phosphorus application by 18–21%, cropland use by 8–11%, and freshwater use by 2–11%) and in most regions, except for some environmental domains (cropland use, freshwater use, and phosphorus application) in low-income countries. Interpretation Approaches for sustainable diets are context specific and can result in concurrent reductions in environmental and health impacts globally and in most regions, particularly in high-income and middle-income countries, but they can also increase resource use in low-income countries when diets diversify. A public health strategy focused on improving energy balance and dietary changes towards predominantly plant-based diets that are in line with evidence on healthy eating is a suitable approach for sustainable diets. Updating national dietary guidelines to reflect the latest evidence on healthy eating can by itself be important for improving health and reducing environmental impacts and can complement broader and more explicit criteria of sustainability. Funding Wellcome Trust, EAT, CGIAR, and British Heart Foundation.

Risk of increased food insecurity under stringent global climate change mitigation policy

Food insecurity can be directly exacerbated by climate change due to crop-production-related impacts of warmer and drier conditions that are expected in important agricultural regions1–3. However, efforts to mitigate climate change through comprehensive, economy-wide GHG emissions reductions may also negatively affect food security, due to indirect impacts on prices and supplies of key agricultural commodities4–6. Here we conduct a multiple model assessment on the combined effects of climate change and climate mitigation efforts on agricultural commodity prices, dietary energy availability and the population at risk of hunger. A robust finding is that by 2050, stringent climate mitigation policy, if implemented evenly across all sectors and regions, would have a greater negative impact on global hunger and food consumption than the direct impacts of climate change. The negative impacts would be most prevalent in vulnerable, low-income regions such as sub-Saharan Africa and South Asia, where food security problems are already acute.Economy-wide GHG emissions reductions may negatively affect food security. Stringent mitigation policies, modelled as carbon prices, are shown to lead to an increase in production costs, food prices and the population’s risk of hunger.

Comparing modeling approaches for assessing priorities in international agricultural research

This article examines how the estimated impacts of crop technologies vary with alternate methods and assumptions, and also discusses the implications of these differences for the design of studies to inform research prioritization. Drawing on international potato research, we show how foresight scenarios, realized by a multi-period global multi-commodity equilibrium model, can affect the estimated magnitudes of welfare impacts and the ranking of different potato research options, as opposed to the static, single-commodity, and country assumptions of the economic surplus model which is commonly used in priority setting studies. Our results suggestthatthe ranking oftechnolo- gies is driven by the data used for their specification and is not affected by the foresight scenario examined. However, net benefits vary significantly in each scenario and are greatly overestimated when impacts on non-target countries are ignored. We also argue that the validity of the singlecommodity assumption underpinning the economic surplus model is case-specific and depends on the interventions examined and on the objectives and criteria included in a priority setting study.