Presented by Louis Verchot (Director of the Soil Research Area at Alliance Biodiversity International-CIAT and Director of MITIGATE+) at "Low-emission food system development in the Mekong Delta: Opportunities, challenges and future pathways", 7 November 2023, Ho Chi Minh City, Viet Nam
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Climate Change Effect on Food Security
Effect of Climate Change
Food Security Components
∙ Reduced crop and livestock yield
∙ Increased heat and drought stress both for crops and livestock
∙ Shorter growing period, reduced grain filling period and terminal heat
∙ Land degradation and loss of soil fertility (saltwater intrusion, flooding)
∙ Higher pre-harvest loss due to disease and pest attack
∙ Negative effect on various physiological processes
∙ Crop failure
Availability
∙ Decreased in nutritional content due to high temperature
∙ Increased mycotoxins due to high temperature and moisture
∙ Adverse weather affect foods in storage and distribution
∙ Reduced water quantity and quality to prepare food
∙ Negative impact on food safety
∙ Higher post-harvest loss both in quantity and quality
Utilization
∙ Increase in price due to low yield or sporadic crop failure
∙ Loss of agricultural income
∙ Disproportionate impact on low-income consumers
Access
• Disruption of food supply due to adverse weather, civil disturbance and social tension
• Yield variability
• Fluctuation in yield, supply and price (2018 drought in Argentina)
• Crop failure due to extreme drought
Stability
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Why the Food System?
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22-35% of all anthropogenic emissions from
food systems (medium confidence) [A3.6]
Projected to increase by about 30–40% by 2050
(high confidence) [A3.6]
Climate change creates additional stresses on
the food systems (high confidence) [A5]
At 2°C the risk of food system instability is very
high (medium confidence) [A5.1]
Integrated supply- and demand-side options can be scaled up in all segments of the food system to
advance adaptation and mitigation climate responses (high confidence) [A5.1]
Diversification in the food system can reduce risks from climate change (medium confidence) [B6.2]
Importance of integrated policies operating across the food system [C2]
Dietary changes can ease the economic burdens of ill health caused by malnutrition (medium confidence)
[D2.3]
IPCC SRCCL
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Food system related solutions to mitigate climate
change
Improving efficiency of food
production.
Consumption of healthy and
sustainable diets.
Minimizing food loss and waste.
Avoiding and reversing deforestation,
land degradation and desertification.
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Food system emissions in Vietnam
Total emissions 2018: 176Mt y-1
or 1% of global emissions
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Land and food system
management can be part of
the solution to tackle climate
change, food security,
nutrition, poverty and hunger.
Enteric
fermentation –
Methane
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GHG emissions from livestock production vary greatly due
to farming practices, animal numbers and type, and food
product.
Source:
FAO
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Three promising enteric fermentation mitigating strategies
Arndt et al., 2022
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Arndt et al., 2022 Scenario analysis conclusions
Agricultural methane emissions must be decreased by 11 to 30% of the
2010 level by 2030 and by 24 to 47% by 2050 to meet the 1.5 °C target.
Globally, only 100% adoption of the most effective product based and
absolute CH4 reduction strategies can meet the 1.5 °C target by 2030 but
not 2050.
Mitigation effects are offset by projected increases in CH4 due to increasing
milk and meat demand.
Notably, by 2030 and 2050, low- and middle-income countries may not
meet their contribution to the 1.5 °C target for this same reason, whereas
high-income countries could meet their contributions due to only a minor
projected increase in enteric CH4 emissions.
Soils –
Nitrous oxide
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N2O emissions are driven by fertilizer application rates and by
the levels of N applied in excess of crop demand
Emission
(Kg
N
2
O-N
ha
-1
)
Nitrogen Fertilizer (Kg-N ha-1)
Tesfaye et al., 2021
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Improving N use efficiency and reducing excess N by 75%
can reduce N2O emissions by ~35% Mitigation
potential
(kg
N
2
O-N
ha
-1
Tesfaye et al., 2021
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Soil C sequestration offers significant opportunities across the
globe with productivity and soil health benefits
Zomer et al., 2017
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Agriculture remains an under represented activity in NDC
adaptation and mitigation commitments
50-70% of the countries with the highest potential for reducing GHG
emissions in livestock and/or soil carbon included mitigation
measures in these subsectors.
• Livestock mitigation priorities include manure management (26
countries), feed management (23 countries) and silvopastoralism
(15 countries).
• Soil carbon, mitigation priorities included wetland management
(35 countries), agroforestry (34 countries) and grassland
management (24 countries).
Many of these activities are also proposed as adaptation measures
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Feasibility of mitigation measures
The cost-effective mitigation potential
50% from forests and other ecosystems,
35% from agriculture, and
15% from demand-side measures.
Governance, economic investment, and
socio-cultural conditions influence the
likelihood that land-based mitigation
potentials are realized.
Roe et al., 2021
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Conclusions
Significant GHG emissions reductions in agriculture are achievable through
reducing emission intensity of production, but population growth and dietary
changes may offset absolute emissions reductions.
Emission reductions consistent with 2030 targets are achievable in many
countries; attaining the 2050 targets will require innovation and systems
transformation.
Net zero agriculture cannot be achieved without sinks!
Governance, economics, and sociocultural factors are the keys to food system
transformations.
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