Transcript Food Security lecture 2

Climate Change
overview
• Caused by build up of green house gases in the
atmosphere
• Mostly carbon dioxide (CO2)
• Released from burning fossil fuels
• CO2 molecules reflect heat back to earth
• CO2 levels approx 280ppm before industrial
revolution
• Currently 390ppm
• Rising at approx. 1 ppm per year
Climate change
how food is affected
• Crops are
– dependant on stable climatic conditions
– specific to each regions climate
– Grown using knowledge specific to certain
climatic conditions
• Climate change affects both the local
farming knowledge and the crops used
Climate change
how food is affected
Climate change affects crops via
–Temperature increase
–Changing weather and seasonal
patterns
–Rising sea levels
–Water availability
Climate change
how food is affected
Temperature
• Higher temperatures globally will lead to
– Increased evapotransporation from plants and soil
– Causing heat stress for plants
• Leads to unsuitable
– Local knowledge
– Crop species/varieties
(B. Parris, 2008, impacts of climate change on food production systems)
Climate change
how food is affected
Temperature
• In mid to high latitudes temperature
increases of 1-3oC can increase yields
slightly with yield decreases at
temperatures after that
– Increase due to carbon fertilization affect
• in tropical and subtropical regions strong
yield depressing effects will probably occur
at temperature increases of 1-2oC
Climate Change
the carbon fertilization effect
• Comes from laboratory experiments which
show that plant growth increases with
increasing CO2
• Could potentially cause increases in crop
yields in mid to high latitudes of up to 8%
• This estimate does not take into account
the effects of increased loses due to pests,
weeds, water scarcity and extreme
weather events
(impacts of climate change on food production systems)
Climate change
how food is affected
Changing weather patterns
• Changing growing seasons
• Shifting ecological niches
• Unpredictable rainfall in both timing and
volume
• Change in pest, weed and disease
populations
(B. Parris, 2008, impacts of climate change on food production systems)
Climate change
how food is affected
Changing weather patterns
• Has the net affect of
– Increasing uncertainty for farmers
– Eroding traditional agricultural knowledge
• i.e. timing of crop planting times
– Requiring new
• Knowledge and technology
• Species and varieties
Climate change
how food is affected
Changing Weather Patterns
Ireland
– East Leinster and East Ulster
• Water stress
– dry summers
– Affecting grass for dairy/beef
– Northwest
• Increased damp cool conditions
– Poor grass, wheat, maize yields
– Improved barley and potato yields
– increased pest and disease problems
– Regular flood and drought damage
(J. Sweeney, 2008)
Climate change
how food is affected
Rising sea levels
•
•
•
•
•
1 to 2 metres rise this century,
possible several metres rise next century
Loss of coastal land
Salinate coastal freshwater aquifers
Impacts directly on available land for
agriculture and water availability for crop
growth
(B. Parris, 2008, www.aosis.info/sid_issues/)
Climate change
how food is affected
Water
• Water scarcity already a problem
• Exacerbated by climate change due to
decreasing rainfall in these regions
• Creation of new areas of water scarcity
– Asia
•
•
•
•
Areas fed by Himalayan glacial melt
Subject to 20-30 years of flooding
Followed by severe water shortage
Affecting in excess of 1 billion people by 2050
(B. Parris, 2008)
Climate change
how food is affected
Water
• Widespread water shortages will almost certainly
have the affect of creating food shortages.
• In Africa alone 75 to 250 million people are
expected to be exposed to water stress due to
climate change by 2020
• In some countries yields from rain fed agriculture
can be expected to decline by up to 50%
(B. Parris, 2008)
Obtaining Food Security
Key Problems
–Dependence on non
renewable energy
sources
–Climate change
–Other factors
Obtaining Food Security
• Non-renewables dependence
– Localising Food Production Globally
– Growing Organic
• Climate change
– Reducing GHG emissions
– Preparing for already probably effects
• Other Factors
–
–
–
–
–
Diversification of seed varieties and livestock breeds
Changing our diet
Remove food from market control
Diversion of grain for biofuel production
Preserving fish stocks
Localising food production
• Reduces food miles
– Food is at your doorstep
• Reduces processing and
packaging
• Thus reducing both GHG
emissions and dependence on
fossil fuels
Growing Organic
• Use of compost instead of NPK fertilizer
• This removes the need for pesticides and
fungicides
• Requires smaller scale but more diverse
farms
• Widespread implementation of biodynamic
farming practices
Growing Organic
• Promotes Biodiversity which helps
stabilise local food systems
– Providing environments for pollinators such as
bees
– Increases supply of wild foods such as elder,
blackberry, damson, rabbit, pigeon, pheasant
– Helps prevents species loss by reducing toxic
chemical usage and providing environments
for species to maintain their numbers
Reducing dependence on non
renewables
• Compost
– Replaces natural gas derived nitrogen fertilizers
– Replaces both potassium and phosphorus fertilizers
• Use every available fertilizer source
– E.g. phosphorus from sewerage
• Reduce water waste
– Use only as much water as can be naturally
replenished
• Using Permaculture
North Korea V Cuba
• Both were dependant on cheap Soviet oil
derived products such as Nitrogen
Fertilizer
• When the Soviet Union collapsed neither
had access to another cheap source of oil
• North Korea endured the worst famine in
living memory
• Cuba underwent serious social change,
but they did not starve
WHY?
North Korea
• Retained modern
agriculture
• Retained communist
structure, rationing what
food was available
• 900,000 to 3.5 million
people died of starvation
Cuba
• Subsidised modern
agriculture with locally
produced fruit and
vegetables
– Everyone encouraged to
grow their own wherever
they could
• Rapidly switched modern
farms to biofarming, using
organic fertilizers to
enrich the soil
Other issues
• Diversity of livestock and crop varieties
• Market control over food prices
• Diversion of food stocks for biofuel
production
• The western diet
• Depletion of fish stocks
Other issues
Seed diversity
• Currently using a limited number of seed varieties for
main crops such as wheat
• This increases the likely hood of a disease threatening
global wheat supply
• E.g. rust fungus in wheat
• Need
–
–
–
–
more diverse seed stocks
Increased funding into research on disease resistance
Creation of a variety of resistant strains to major diseases
Particularly important due to increased threat of disease as a
result of climate change
Other issues
market control
• Significant price fluctuations of staple
foods via price speculation on world
markets
• Causes price of basic foods (sugars, oils
and grains) to increase rapidly
• Pushes people below the bread line
• Need to regulate market to ensure food
prices remain stable/reflect global
production
Other issues
Biofuels
• 40% American corn harvest diverted to
biofuels
• Increases price of corn
• Pushes people below the bread line
• Serious increase in biofuel use in Europe
imminent
– In order to meet carbon emissions targets
Other issues
the western diet
• High in meat proteins
• 20% of global green house emissions come
from intensive cattle rearing
• High in starch
• Greater the diversity in your diet, the less
chance of any one deficit causing food insecurity
– E.g. An Górta Mór
• UNHEALTHY!
– Greater mortality
– Greater cost to health system
Other issues
Depletion of fish stocks
• 90% of the fish stocks have been depleted since
the 1900’s.
• Demand for specific species causing over fishing
• Shift focus to sustainable species from lower
down the food chain
– Dublin bay prawn (langoustine)
– Mackerel
– Herring
• Need creation of more marine protected areas to
allow for fish stock recovery
• Development of sustainable aquaculture
Obtaining food security
conclusion
•
•
•
•
Short term
Fix food price uncertainty
due to stock markets
Assign real value to fish
stocks
End 1st generation biofuel
production
Create marine protected
areas
•
•
•
•
•
•
•
Long term
2nd generation biofuels
disease resistant crops
crops adapted to local
climate
Local agriculture
Biodynamic farming
permaculture
Rethink our diet