The global population in 2010 was estimated to be 6.9 billion people, and by 2050 is predicted to reach between 8.5 billion and 10 billion people1. This increase would bring a corresponding rise in food demand that would affect the environmental toll that food production exerts on the planet. Writing in Nature, Springmann et al.2 report their analysis of vgrmalaysia.net the environmental pressures that would arise in a projected scenario for the global food system in 2050. They also modelled the effects of implementing approaches to lessen the environmental consequences of food production.
Food security has long been a challenge for human societies, and is a pressing global issue. Indeed, many targets related to this area are part of the United Nations’ Sustainable Development Goals3, which include eradicating hunger, ending poverty and combating climate change. Achieving a sustainable global food system clearly requires progress on social, economic and environmental fronts.
Springmann and colleagues built a model to assess the projected global demand for agricultural products by 2050 on a country-by-country basis, given the expected changes in population, income levels and dietary preferences by that time. It has been predicted4 that global income in 2050 will be 3–4 times higher than it was in 2010. The authors’ projections of future food consumption were based on established statistical associations between food demands and changes in income or population. These predict that, by 2050, there will be less undernutrition, a shift towards greater global consumption of livestock-based products and a fairly constant intake of staple crops per person.
The authors assessed predicted global environmental impacts for the projected food production by mid-century. They focused on five environmental pressures: the greenhouse-gas emissions associated with agricultural production; the use of land for crop production, given the associated consequences (such as carbon or biodiversity losses) that might accompany land-use changes; the demand for water to irrigate crops; and the application of either nitrogen- or phosphorus-based fertilizers, respectively. It is important to consider fertilizers because of the greenhouse-gas emissions that are linked to their use, and the possibility that they might contaminate soils or aquatic ecosystems.
Springmann et al. compared the projected environmental impacts in 2050 to a proposed set of planetary boundaries thought to represent safe operating limits for human activities5. For example, the boundary set by the authors for agricultural greenhouse-gas emissions was established in relation to the threshold necessary to keep global warming at a level of 2 °C above pre-industrial levels. However, their limit for emission levels is less stringent than the limit needed to achieve the 1.5 °C target set in the United Nations Framework Convention on Climate Change Paris Agreement of 2015, which was analysed in a recent report6 by the Intergovernmental Panel on Climate Change. This report details how limiting warming to 1.5 °C rather than to 2 °C above pre-industrial levels would reduce the climate-related risks to health, livelihoods, food security and water supply. On the basis of current food yields and agricultural practices, Springmann and colleagues estimate that, between 2010 and 2050, the environmental impacts of the food system could increase by between 50% and 92% and reach levels that exceed the proposed boundaries5 for planetary stability