3. Climate Change and Food Production

• Food production can be a contributor to greenhouse gas emissions, and therefore a contributor to climate change.
• Changing patterns of floods, droughts and agricultural pests because of climate change can also affect food production, reducing agricultural yields and increasing food insecurity and associated health conditions.

Scientists, researchers and policymakers have brought increased attention to the complex nexus between climate change, human health, and food, energy and water systems, with a particular focus on nutrition and diet-related health.^[1] Public health researchers describe obesity, undernutrition and climate change as a global syndemic (or synergy of epidemics), as they interact with each to produce complex effects, share common underlying societal drivers, and affect most people in every country and region worldwide.^[2] Research has demonstrated how the dominant industrialised food system — the process of growing, producing, distributing, retailing, marketing, consuming and disposing of food — makes a significant contribution to anthropogenic planetary change, while at the same time, food production, nutrition and diet-related health are being negatively impacted by climate change. For example, food production is one of the largest contributors to climate change, with agriculture directly contributing approximately 15 to 23% of all greenhouse gas emissions, rising to approximately 30% when other food system processes and impacts (such as food waste) are included.^[3] Livestock production alone accounts for 19% of greenhouse gas emissions, with meat and dairy products (the consumption of which is increasing globally) requiring more resources and generating larger methane emissions than plant-based alternatives.^[4] The globalisation of food systems has also relied on energy from fossil fuels for large-scale agricultural production, as well as long-haul transportation of food products around the world.^[5] Other negative environmental impacts from industrialised food production include soil erosion, deforestation and biodiversity loss caused by large-scale land clearing and over-irrigation of rivers.^[6]

Simultaneously, climate change has already impacted food production and is predicted to have serious, long-term impacts on the resilience of the food system.^[7] In Australia, higher temperatures, changing rainfall patterns and worsening drought and flood conditions are having a significant impact on agricultural industries and farm productivity. Crop production is also being impacted by changes in the incidence of pests and increases in the frequency and severity of extreme weather events, which can damage or wipe out harvests. In addition to drought and water scarcity, fruit and nut crops produced in warm, temperate regions are threatened by increasing temperatures during winter, as sufficient winter chill accumulation is necessary for critical milestones in crop development.^[8] Western Australia’s farming region has experienced the greatest decrease in productivity in Australia due to climate conditions, which lowered productivity in the state by an average of 7.7% between 2000 and 2015.^[9] Globally, climate change is anticipated to lead to reduced crop yields, as well as reductions in the micronutrient content of staple crops.^[10]

The decreasing supply of fresh, nutritious food will have serious implications for food availability and affordability, thus impacting food security, nutrition and the prevention of NCDs. Increases in food insecurity, nutrient deficiencies and chronic undernutrition are most likely to impact those already at risk of these conditions, which in Australia include people in lower income groups, asylum seekers and refugees, Aboriginal and Torres Strait Islander people, and residents of remote communities, where it is already difficult to access affordable, good quality, fresh food.^[11] In low- and middle-income countries, severe undernutrition and malnutrition in early life causes stunting of physical growth as well as increased susceptibility to diarrhea and infections.^[12] Malnutrition and food insecurity are also predictors for obesity later in life, as well as the development of cardiovascular disease, diabetes and other metabolic disorders.^[13] Further, globalisation of the food system and other commercial drivers have increased the availability of, and people’s exposure to, cheap, highly processed, energy-dense and nutrient poor foods.^[14] These food products are likely to dominate the food supply as fresh produce becomes scarcer and more expensive,^[15] yet consumption of these products is identified as a key risk factor for health conditions such as high blood pressure, obesity and NCDs.