Climate Change and Elevated CO2 Impacts

Greenhouse Gases

  • Composition:
    • Nitrous Oxide: 7\%
    • Methane: 23\%
    • Carbon Dioxide: 70\%, with 75\% from fossil fuel burning and 25\% from changes in land-use.

Sectors Affected by Climate Change

  • Agriculture: Expected decline in food production.
  • Fisheries: Migration of fish and changes in spawning habitats.
  • Health: Malnutrition, water and insect-borne diseases, drinking water scarcity (especially in atolls).
  • Transport: Damage to roads, bridges, and wharfs.
  • Forestry/Environment: Bushfires, wildlife migration, loss of flora and fauna (genetic diversity).
  • Social & Economic: Rise in law and order problems.
    • Food Security & Livelihood: Affects everyone.

Consequences and Trends of Climate Change

  • Temperature rising.
  • Sea level changing: leads to loss of habitats and homes.
  • More frequent extreme weather events.
  • Ecosystem change: loss of biodiversity (species loss).
  • Impacts on People With Disabilities (PWD).

Effects of Elevated CO2

  • Questions to consider:
    • Will more or less CO2 be sequestered by forest trees or in soil as CO2 levels rise?
    • Will elevated CO2 alleviate other stresses (e.g., ozone, drought, low fertility)?

Climate Change Impacts on Food Supply & Agriculture

  • Part 2 Focus: Food supply & Agriculture

Lecture Outline

  • Free Air Carbon Dioxide Enrichment experiment (FACE)
  • Ecological Impacts of elevated CO2 on plants
  • Other impacts of elevated CO2

Free-Air Carbon Dioxide Enrichment Experiments

  • FACE (1990s):
    • Locations: US, Switzerland, New Zealand, Germany

Free-Air CO2 Enrichment (FACE) Sites

  • CCM USA
  • MUSA
  • Call
  • Durham, North Carolina, UNA
  • Hungary

Ecological Lessons from FACE: Plant Growth (+)

  • Elevated CO2 increases the rate of photosynthesis.
  • Plants grow larger with more branches.
  • More and thicker leaves.
  • More extensive roots.
  • More flowers & fruits (increased yield).

Ecological Lessons from FACE: Efficient Use of Water by Plants (+)

  • Limits opening of stomata, reducing evaporation.
  • Increasing CO2 for photosynthesis.
  • More plants in drier conditions.
  • More ground cover, reducing erosion.

Ecological Lessons from FACE: Soil (+)

  • Root decomposition decreased.
  • Sequestration increased by Soil by 24\%.
  • 50\%

Ecological Lessons from FACE: Plants Overcome Resource Deficiencies (+)

  • Even in the face of severe nutrient deficiencies in soil, growth increases.
  • Due to extensive roots caused by CO2 induced growth.
  • Enhanced activity of nitrogen-fixing bacteria.

Ecological Lessons from FACE: Change in Chemical Composition (-)

  • Less uptake of nitrogen.
  • Protein will decrease.
  • Low mineral availability.
  • Reduced mineral availability to higher consumers.

Ecological Lessons from FACE: Ground-Level O3 (-)

  • Elevated CO2 increasing pollutants.
  • Ground-level O3 damages leaves, decreases growth & photosynthesis.

Impact of Elevated CO2 on Agricultural Crops

  • Geography will play a role in how agricultural benefits from impacts of climate change.

Impact of Elevated CO2 on Agricultural Crops

  • Agricultural losses in the tropics.
  • Gains in the north.
  • GDP increases in North

Impacts of Climate Change on Food Security

  • Dimensions of food security:
    • Food availability
    • Food accessibility
    • Food utilization
    • Food systems stability

Impacts of Climate Change on Food Security: FAO

  • FAO’s vision: a world where most people can obtain the food they need for an active and healthy life, with social safety nets for those who lack resources (FAO, 2007f).

Impacts of Climate Change on Food Security: FAO

  • Food security exists when all people at all times have physical or economic access to sufficient safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life (FAO, 1996).

What is Food Security?

  • FAO, 2001: Food security exists when all people, at all times, have physical, social, and economic access to sufficient, safe & nutritious food which meets their dietary needs & food preferences for an active healthy life.

Impacts of Climate Change on Food Security

  • Impact on:
    • Human Health
    • Livelihood assets
    • Food production & distribution
    • Purchasing power & market flows
  • Vulnerable and food-insecure populations are likely to be the first affected.
  • Agriculture-based livelihood systems face immediate risks like increased crop failure, new patterns of pests and diseases, lack of appropriate seeds, and loss of livestock.
  • People living on coasts, floodplains, mountains, drylands, and the Arctic are most at risk.

NARI

  • Hybrid Taros (4 var)-TLB tolerant
  • Lowlands S/potatoes (10 acc.)-
  • Cassava (4)- drought / low cyanide
  • African Yam (2 var)-drought
  • T Rice - Corn (OP)
  • Other minor imported Veges..

SOG

  • 1

SIWAE

K

  • 370

Climate Change & Food Security: Agriculture

  • Agriculture + Food + Work

Climate Change & Food Security

  • Adaptation + Mitigation = Food security

Other Impact of Elevated CO2 on Agricultural Crops

  • Shift in climate.
  • Help identify crops that can deal with climate shift.
  • Increase irrigation needs.
  • Reduced income for subsistence farmers.
  • Increase in food prices.

Other Impact of Elevated CO2 on Agricultural Crops

  • Elevated CO2 beneficial to invasive plants.
  • Climate change may result in effective biological controls.
  • Study by Reeves et al. 2015.

Biological Impact of Elevated CO2 on Plants

  • Positive impact on photosynthesis, yield & overcoming stressful conditions.
  • Effects are not uniform; some species will show less response to elevated CO2 than others.
  • Effects on growth and composition of natural plant communities will vary.

Future Outlook

  • CO2 is increasing + Uncertainty = Plants' productivity

Reference

  • Enerst, J & Gwabu, C (2015). NARI’s programs towards climate change public lecture presentation.
  • Henderson, R (2006). The rough guide to Climate change. New York: Rough Guides Limited.
  • Houghton, J. (2015). Global warming: the complete briefing. (5th ed.). United Kingdom: Cambridge University Press.