Climate Change and Agriculture

Transcription

1 Climate Change and Agriculture FAB-465 Lecture 8 Carbon footprint Outline Greenhouse gases and greenhouse effect Climate change Direct impact of climate change on agriculture GHG emissions and their impact on the environment 1

2 Carbon foot print Carbon footprint (FP): is the total set of GHG (greenhouse gas) emissions caused directly and indirectly by an individual, organization, event or product (UK Carbon Trust 2008). Best estimate of full climate change impact of something Carbon Usually talking about CO2e (CO2-eq) not actually just carbon dioxide Footprint Total impact Everyone in this room has a FP CO 2 Equivalent Measure used to compare the emissions from various greenhouse gases based upon their global warming potential. E.g Global warming potential of methane over 100 years is ton of methane = 21 tons of carbon dioxide 2

3 Greenhouses Gases (GHGs) Greenhouse gases are made out of: water vapour carbon dioxide methane nitrous oxide ozone chlorofluorocarbons They are all natural gases, but extra greenhouses gases can be made by humans polluting. 3

4 Total climate change impact of all greenhouse gasses caused by item or activity 8 4

5 Climate Change Complex set of changes in different environmental factors Rise in temperature Reduced precipitation Increased CO 2 concentration Frequency, severity & extent of extreme events Floods and heavy rainfalls, extended droughts etc 5

6 Climate system Greenhouse Effect 6

7 Direct impact on Agriculture Climate change affects the physiology of crop plants which may lead to economic losses Changes in crop productivity due to diseases Fluctuations in rainfall Changing weather patterns Increased CO 2 Altered physiology & morphology of host under elevated CO 2 Changes in interception of light and precipitation Modification of canopy structure and microclimate to influence disease epidemiology Classic Disease Triangle 7

8 How do we measure Climate Change? General Circulation Models (GCMs) Simulate climatic processes Computer programs used for estimating impact Take all known environmental and nonenvironmental variables into account Simulation of dynamic and thermodynamics of atmosphere, oceans, land and ice cover Can be run at different GHG concentrations Impact of Humans Like all living things, humans exploit their surroundings for resources. The world s human population has passed 8 billion and continues to increase. The growth in the human population and the increase in the standard of living are putting strains on the global environment. 8

9 Here are some of the ways in which this is happening non-renewable energy resources, such as coal, oil and natural gas, are being used up rapidly raw materials are being used up rapidly more waste is being produced more pollution is being caused Country CO 2 emissions [14] Emission 14] World 34,500, China 9,860, United States 5,190, India 1,970, Russia 1,770, Japan 1,320, International transport 1,060,000 - Germany 810, South Korea 640, Canada 560, United Kingdom 490, Mexico 490, Indonesia 490, Saudi Arabia 460, Brazil 460, Australia 430, Iran 410, Italy 390, France 370, South Africa 330, Poland 320,

10 Direct vs. indirect emissions Direct emissions of an item Manufacturing process Transportation of item to retailer Direct: burning natural gas in a furnace Indirect emissions Everything else Example: offices in the factory use paper clips made of steel that were mined and have their own carbon footprint and using electricity generated by a coalfired power-plant 19 Typical personal carbon sources Driving a car Lights and heat Travel Food Consumer goods Building materials 10

11 The world-wide average is 4 tons of carbon dioxide (CO2) per person per year The average of all industrialised nations is about 11 tons of carbon dioxide (CO2) per person per year In the medium and long term, a world-wide average emission of maximum 2 tons of carbon dioxide (CO2) per person per year must be targeted. This amount is nowadays considered to be the maximum allowed quantity for a sustainable living on earth. The international Global Carbon Project consortium has announced that global carbon dioxide emissions in the atmosphere will reach a record high of 35.6 billion tons in 2012 Context for numbers 1 gram of CO 2 e would be produced if you burned a pea sized blob of gasoline 1 Kilogram (2 lbs) of CO 2 e would be produced if you burned 2 cups of gasoline 1 Ton of CO 2 e would be produced if you burned 60 gallons of gasoline 11

12 Which type of orange juice would have the highest carbon footprint per pint? 1. Locally made at the restaurant 2. Store bought, locally bottled 3. Store bought, bottled elsewhere, imported long distances 23 Which food would produce highest carbon footprint for cycling a mile? 1. Air-freighted asparagus 2. Beef 3. Bananas 24 12

13 The carbon footprint of manufacturing a new car is compared to the carbon footprint of driving that car over its lifetime 1. Very small 2. Roughly equivalent 3. Very large 25 Breakdown 13

14 How do we remove this CO 2? Carbon sink: is a reservoir of carbon that accumulates and stores carbon for an indefinite period. The main sinks are: Absorption of carbon dioxide by the oceans Photosynthesis by plants and algae to turn the carbon into plant matter Injection of CO 2 emissions deep into geological subsurface Bananas Bananas have very low carbon footprints compared to other foods Grown in natural sunlight (not in a heated greenhouse) They don t spoil quickly So instead of shipping them by plane, you can ship them by boat (1% the carbon footprint of flying) No packaging Total = 80 g CO2e if shipped from across the world 28 14

15 ADAPTATIONS TO CLIMATE CHANGE Annual vs Perennial crops What are the advantages and limitations? Agricultural practices Pests Food processing transport Tillage vs no tillage 15