Climate Change and Food Systems

Introduction to Climate Change and Food Systems

• This is an introduction to climate change and global food systems.

What is Climate Change?

• Climate change involves long-term shifts in temperature and weather patterns.
• Climate change happens naturally via volcanoes and variance in solar activity.
• Human activities since the 1800s are a major driver of climate change.
• The Earth's surface is now about 1.2°C warmer compared to the late 1800s.
• The last decade between 2011-2020 was the warmest on record.
• The last four decades have been warmer than any previous decade since 1850.

Evidence of Climate Change

• The rate of warming since the mid-20th century is unprecedented.
• Modern climate began with the end of the last ice age, about 11,700 years ago.
• Human activities drive current warming trends, mostly via fossil fuels and deforestation since the mid-1800s.
• Human actions significantly increased CO2 and greenhouse gases.
• Increased greenhouse gases trap heat and warm the atmosphere, oceans, and land.

Causes of Climate Change

• Greenhouse gas emissions, like carbon dioxide, nitrous oxide, methane, chlorofluorocarbons, and water vapor, cause climate change.
• Human activities, like burning fossil fuels, deforestation, and agriculture, increase GHGs.
• Greenhouse effect where trapped gases raise temperatures.
• Temperatures trigger changes, impacting the natural world and human societies.
• Burning coal, oil, and gas produces carbon dioxide and nitrous oxide.
• The climate is unbalanced through deforestation by eliminating the trees that absorb CO2.
• Livestock releases methane, and nitrogen fertilizers produce nitrous oxide emissions.
• Fluorinated gases are emitted from products, and have a very strong warming effect, up to 23,000 times greater than CO2.

Effects of Climate Change

• Increase of frequency and severity of floods, droughts, hurricanes, and wildfires.
• Ice caps and glaciers are melting and causing rising sea levels.
• Declining agricultural productivity and rising food prices cause food insecurity.
• Habitat destruction increases species extinction and biodiversity loss.
• Increased heat-related illnesses, respiratory diseases, and spread of vector-borne diseases.

Understanding Food Systems

• Food systems encompass the networks needed to produce, transform, and deliver food to consumers.
• "Food systems" includes all elements and activities related to producing food and consuming food.
• These systems also have economic, health, and environmental outcomes.
• Food systems include activities like farming, fisheries, and aquaculture.
• Food systems include packaging and value addition.
• Supply chains and food miles are integral to distribution.
• Dietary patterns and cultural preferences impact food systems.
• Disposal, recycling, and composting are essential for waste management.

Food System Drivers

• Climate, biodiversity, and soil health are key biophysical drivers.
• Societal preferences determining desirable food and gender norms around food consumption are cultural drivers.
• The presence of infrastructure ensures the effective transport of food.
• Research and development innovations impact food systems.
• Demographic changes in urbanization and family sizes are important factors.
• Economic opportunities to support food and agriculture are important.
• Political and economic factors, like income growth, play a role in determining a food system.

Impact of Climate Change on Food System

• Climate change has impacts on all components of food systems.
• Agriculture, forestry, fisheries, food industries, and value-adding activities such as production, processing, distribution, consumption, and recycling are affected.
• Food systems encompass land use, storage, transport, packaging, processing, retail, and consumption.
• Food systems contribute to 21-37% of global GHG emissions.
• Agriculture is a major driver of these emissions.
• Climate change reduces agricultural productivity by 21% since 1961.
• Cereal yields have decreased by 2–5% globally over the last four decades.
• Maize in Africa, Asia, and the Americas is impacted.
• Millet and sorghum in West Africa show losses of 5–20%.
• Higher maize losses occur in Eastern and Southern Europe.
• Despite coping actions, crop losses continue.
• Yield stability is compromised due to weather variability.
• A 15-35% decrease fish and shellfish production by in acidification and temperatures.
• The largest losses are expected in hot, dry regions.
• Livestock productivity and reproduction are reduced due to heat stress and droughts.
• Marine fish populations' sustainable yield has been reduced by about 4%.
• Global cereal prices are projected to increase between 1% to 29% because of climate change.
• The cost of all legumes, fruits, and vegetables are affected.

Food Utilisation and Safety

• Diet and food quality can cause 529,000 climate-related deaths.
• Higher CO2 reduces protein and mineral content in cereals and degrades food quality.
• Rising temperatures favor the spread of pathogens and mycotoxins, increasing food loss and waste.
• Climate change is projected to increase mycotoxins from tropical and sub-tropical to temperate zones.
• Reduced water quality to affect food utilisation.

Impact of Food Systems on Climate Systems

• Food systems are responsible for 21-37% of global GHG emissions.
• 16 Gt CO2 eq/year is emitted from food systems (~one-third of global anthropogenic emissions).
• Agriculture, land-use change, processing, and disposal cause food system emissons.
• Animal agriculture accounts for 18% of global emissions.
• Methane accounts for 25% of emissions, and nitrous oxide is 31%.
• Cattle (42% beef, 20% dairy), pigs, poultry, and small ruminants contribute.
• Manure production and disposal are large contributors.
• Animal agriculture emits 25% methane, 32% from land use and land use change, and 31% nitrous oxide from manure and slurry.
• 931 million tons of food waste is generated annually (61% households, 26% catering, 13% retail).
• Food waste contributes 8–10% of global GHG emissions.
• 1.26 billion people could be fed by not wasting food.

Sustainable Food Production

• Conventional agriculture and food production systems contribute significantly to climate change through various elements, including:
  • Livestock production
  • Pesticides
  • Manure and chemical fertilisers
  • Large quantities of water
  • Ploughing of soil
  • Food wastage
  • Food packaging
  • Deforestation
  • Food transportation
  • Energy costs of machinery

Climate Change Adaptation and Mitigation in Food Systems

• Adaptation involves coping with climate change effects and managing climate impacts to assure food security and resilience to climate stressors.
• Adaptation includes diversifying crops, implementing efficient irrigation, climate-resilient crop variety, soil management to improve fertility, and early warning systems for extreme weather.
• Mitigation involves reducing GHG emissions and enhancing carbon capture, reducing the food system's impact on climate and enabling sustainable production.
• Mitigation comprises of reducing food waste, implementing practices such as organic farming, efficient livestock management, lower carbon footprints through plant-based diets, and the use of renewable energy.
• Sustainable agriculture practices include crop rotation, agroforestry, and no-till farming.
• Further agriculture improvements include reduced synthetic fertilizers and pesticides, soil health improvement, and integrated pest management.
• Sustainable Agriculture enchances biodiversity, reduces soil erosion, sequesters carbon, maintains soil moisture, and decreases the use of synthetic inputs.

Carbon Farming

• Carbon trading boosts soil nutrition.
• Manure on fields reduces production.
• Synthetic fertilizers increase CO2 emissions.
• Cultivation of rice is detrimental to the climate.
• Enteric fermentation has a negative effect.
• Burning savanna & crop residues has a negative effect.
• No-tillage methods are important for soil and climate.
• Water resource management will reduce soil pollution.
• Crop rotation has positive impacts.
• Carbon-friendly polution reduction and practices and fixation of nitrogen are beneficial.

Ways to Mitigate the Impacts of Climate

• Crop rotation involves different types of crops sequentially on the same land to improve soil health and reduce dependency on chemical inputs.
• Crop rotation enchances soil fertility.
• Also reduces soil erosion and compaction.
• Manages pests and disease cycles.
• Biodiversity is enhanced.
• There is better water retention.
• Reduces greenhouse gas emissions, increases soil carbon sequestration and decreases nitrous oxide emissions.
• Builds resilience to extreme weather and also promotes sustainable agricultural practices.
• Cover-crops involve planting crops specifically to protect and enrich the soil
• Farmers plant cover crops improve in between, or during, crop off-seasons.
• Improved water reatention and and fertility are achieved.
• Vertical farming a modern method of growing crops in stacked layers with nutrient-rich water solutions, enabling year-round food production