Energy Use by Agriculture

Transcription

1 Energy Use by Agriculture Robert S. Lawrence, MD Director, Center for a Livable Future Johns Hopkins Bloomberg School of Public Health March 12, 2009 Average U.S. farm uses 3 kcal of fossil energy to produce 1 kcal food energy Feedlot cattle fossil energy input is 35 kcal/kcal of beef protein produced Transporting, processing, and packaging food uses large amounts of energy JHU Center for a Livable Future gallons of oil equivalents per person per year in US 31% for manufacture of inorganic fertilizer 19% for operation of field machinery 16% for transportation 13% for irrigation 8% for raising livestock (not including feed) 5% for crop drying 5% for pesticide production 8% miscellaneous Fossil Fuels & Agriculture Does not include energy for packaging, refrigeration, transportation to retail outlets, and household Food Security 2025 population of 8.3 billion people will require an additional 2.6 billion tons if current per capita consumption remains constant. If the one billion hungry poor have improved diets, including some animal protein, food demand will double to about 9 billion tons. In 1992 UNCED identified global warming and loss of biodiversity as major threats to food security. Today it is more likely that energy and water availability will be more critical for a sustainable food supply. Energy Inputs for Processing Foods Canned fruits/vegetables 575 kcal/kg Frozen fruits/vegetables 1,815 kcal/kg Breakfast cereals 15,675 kcal/kg Chocolate 18,591 kcal/kg 1

2 US-based calculators that input food, output GHGs (as proxy for energy use): Berkeley Institute of the Environment Economic Input-Output Life Cycle Assessment Metric tons CO2e per $1,000 Breakfast cereal manufacturing Maize Effects on Agriculture Mid-to-High Latitude Low Latitude 1-3 o C Some higher latitudes: neutral or slight benefit Lower latitudes: detrimental Wheat > 3 o C Detrimental in all latitudes Carnegie Mellon University Green Design Institute. (2008). Economic Input-Output Life Cycle Assessment (EIO-LCA) model. Retrieved June 13, 2008, from Rice APO & Agriculture: The Green Revolution , world grain production 250% Virtually all productive land on planet is now exploited for agriculture There was a 50 fold increase in energy input New models used industrial agriculture that lead to degradation d of land, water, and soil On average, we invest 10 kcal of fossil fuel energy for every 1 kcal of food energy derived Ratio worse for meat, can be > 100 In U.S. in 1900, 39% of population involved in farming, now 0.3% (9.1% if processing, preparation and serving included in food system) US Bureau of Labor Statistics. May 2005 National Occupational Employment and Wage Estimates (calculated) Already Happening Drought, extreme weather Earlier spring leaves, bird migration, egg laying Poleward/upward shifts in species geographic ranges Pests, invasive species Biodiversity loss Broccoli in Greenland New Plant Hardiness Zones ; photo Hamish Wilson from Env Health Perspect 113:8; Aug

3 Expected Impacts: Food & Agriculture Higher food prices Decrease in amount & variety of food Decrease in nutrition, especially for poor Changes in food retailing More household food production, preservation, preparation What We Can Do About It April 9, 1973 Adapted from John Kaufmann, Oregon Dept Energy Economic impacts Less consumer spending Business failure Hardship for marginalized & vulnerable populations Social impacts Stress Conflict More demand for social services Less government revenue Fuel shortages Oil & natural gas Price increases Transportation Manufacturing Food Opportunities Demand for efficient products & services Advantage for efficient businesses & communities Impact Pathways Adapted from John Kaufmann, Oregon Dept of Energy Sustainable Agriculture Small farms using fewer off farm inputs Integrate animal & plant production where appropriate Miti Maintain higher h biotic diversityit Emphasize technologies appropriate to the scale of production Make the transition to renewable sources of energy, weaning from fossil fuels Who Is Affected Everyone The poor Children Elderly People in affected areas lacking adaptive capacity, including Areas such as Arctic, Sub Saharan Africa, Asian Megadeltas Land types such as island/coastal, dry tropics, low latitude agriculture, etc. Local Food for Global Food Security Policies of Localization: Gradual introduction of import controls to protect those goods which can be produced domestically from imports which could threaten the recovery and diversification of national agricultural systems Eco taxation to ensure the real costs of environmental damage, unsustainable production methods and long distance trade are included in the cost of food 3

4 Local Food for Global Food Security Greater support for farmers to enable them to prosper and produce healthy food using environmentally sustainable farming methods Ending long distance transport and live exports of animals Restriction of the concentration and market power of the major food corporations and retailers through new competition laws, fair prices paid to farmers & charged consumers Greenhouse Gas Emissions* Total: 30.9% WORLD U.S. Activities related to agriculture: 10% Forestry incl. deforestation: 14.8% Total: 24.8% *anthropogenic (human-caused), CO 2 -equivalent IPCC Local Food for Global Food Security Residual long distance trade in foods which cannot be produced in a region (bananas, tea, coffee) to follow the principle of Fair Trade Miles & use of most efficient transport Fair Trade Miles to be linked to a guaranteed quantity of goods to be purchased by each buying country, within a guaranteed range of prices Reorientation of the goals of international trade and aid to build sustainable economies U.N. F.A.O Livestock s Long Shadow Livestock production: 18% world greenhouse gas emissions More than transportation UN FAO 2006 Life Cycle Assessment (LCA) Methane 25x Global Warming Potential of CO 2, Ruminant enteric fermentation causes 71% US agricultural emissions (EPA estimate) Manure cesspits Rice paddies Sonesson, U. Life Cycle Based Research In Food and Agriculture. Göteborg, Sweden: SIK - Swedish Inst. Food & Technology. UN FAO 2006, EPA 2005; IPCC

5 Nitrous Oxide 298X global warming potential of CO 2, stays in atmosphere 114 yrs Nitrogen based fertilizers a top source 51% US nitrogen is used for fertilizers for animal feed/pasture Alternate Energy Sources Biofuels from crops FOOD PRICE CRISIS IMPACT? Tradeoffs in land use Developing country economies Environmental impacts Reduction in GG emissions? Methane digestion (manure) Generally requires animal concentration UN FAO 2006, EPA2005, IPCC 2007 Carbon Dioxide I Soil and plant life trap greenhouse gases Conservation programs Agricultural practices Land clearing, tilling, poor soil mgt, others Deforestation Of previously forested land in Amazon, 70% now pasture; much of the rest now feed crops Greenhouse Gas Emissions From Food U.S. other, 9% Chicken/fish/eggs 10% Red meat, 30% Dairy, 18% fruits/vegs, 11% cereals/carbs, 11% Red meat + Dairy = 48% Weber C, Matthews S. Food-miles and the relative climate impacts of food choices in the United States Environ. Sci. Technol. 42 (10), UN FAO 2006 Reformatted from Weber/Saunders in ES&T, 2008 Carbon Dioxide II Energy US food production responsible for: 10.5% US energy use 17% US fossil fuel use Food processing, transportation, cooling, heating, light, storage, facility needs, etc. Manufacturing Fossil fuel based pesticides, fertilizers, packaging, food items, plastic bags, etc Heller & Keolian 2000; Unruh 2002; Pimentel & Pimentel 1996 CAFO (factory farm) vs. Grass fed CAFO Versus More energy (CO2) More inorganic fertilizers (N2O) More livestock manure stored (CH4) Grass fed More enteric emissions (CH4) Type of feed Slower growth; more animals = more emissions More land use Energy use isn t everything! CAFO production very harmful for other environmental and health reasons 5

6 Eat: Individual Level Energy Use Less meat/dairy More seasonal, lowprocessing, local, organic (not greenhouse/ air freight) Long shelf life Reduce refrig, freezing Reduce trips to store Less packaging / bring own bag Less and waste less Challenges include: Hard to make and sustain Food environment not supportive Not always clear what to buy Ounces Meat Consumption Recommendations 8.8 Current consumption 5.5 USDA recommended 64% reduction from current Climate Change recommendation (Lancet) Red meat CC recommendation (Lancet) Lancet: Per capita consumption to stabilize livestock greenhouse gas emissions at 2005 levels by 2050 (McMichael et al 2007; also USDA, USDA ERS) 1.8 Public Health & After Peak Oil Mitigation Co Benefits Often same eating patterns benefit both nutrition, fossil fuel energy demands Eat less Less meat Less processed, etc Healthier, more sustainable food system Addressing climate: long term public health benefits Cutting Back on Meat IPCC Chair, Rajendra Pachauri: Give up meat for one day (per week) initially, and decrease it from there. In terms of immediacy of action and the feasibility of bringing about reductions in a short period of time, it clearly is the most attractive opportunity." anddrink Government Level Promote sustainable food production, access, affordability Cut subsidies for meat production Support sustainable food programs Conservation Reserve Program Create incentives for localization Reduce food from deforested lands Reduce food from deforested lands Incentives/financial support to small holders Research $ Labeling and standards Regulate methods, energy efficiency Communication campaigns Food/ag policy integrated into energy use policy 6