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Intergovernmental Panel on Climate Change - IPCC Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely [>90% probability] due to the observed increase in anthropogenic greenhouse gas concentrations. 4th Assessment Report 2007.
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Intergovernmental Panel on Climate Change - IPCC Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely[>90% probability] due to the observed increase in anthropogenic greenhouse gas concentrations. 4th Assessment Report 2007 Joint statement of 13 national academies of science (1) Anthropogenic climate change is real (2) Mitigation is urgent (3) Adaptation will be necessary. Opportunities for climate mitigation through forestry and agriculture in Florida S. Mulkey May 2008
Potential capital losses William D. Nordhaus. 2006. The Economics of Hurricanes in the United States. NBER 12813, 47pp. Florida -Ground Zero Miami-Dade County: Nonlinear rise of 3 to 5 ft by 2100.
Emissions for “business-as-usual” 80% cut in emissions by 2060 Emissions target We need at least 7 wedges (More than 7?) Mitigation - Can we do it? Land Management William Chameides
The Arizona climate action plan • The Bottom Line • • The plan contains a portfolio of 49 recommendations that, if implemented, will cut Arizona’s GHG emissions almost in half by 2020 and provide $5.5 billion in net savings to the economy. (Center for Climate Strategies) • Thirty percent of Florida’s energy needs can be met by efficiency and renewables by 2023 and save about $28 billion.(ACEEE, 2007)
Initial strategy for Florida emissions mitigation • Mandates and incentives for promoting solar & biofuels • Renewables portfolio for power generation • Market based incentives for compliance including cap-and-trade and/or a carbon tax • Greenhouse gas inventory including biological flux • Climate action plan with emissions targets • Greenhouse gas reporting registry • State standards for energy production efficiency • Appliance efficiency standards • Green building standards for state buildings • Conservation and alternative energy markets will create economic opportunity; carbon markets will help determine land use options.
Mandatory caps with carbon market trading “We are committed to a pathway that will slow, stop and reverse the growth of US emissions while expanding the economy.”
Carbon markets make money • Emitters purchase allowances from other emitters who are below their regulated limit. • Emitters purchase carbon offsets from enterprises that remove GHGs from the atmosphere. • Displacing fossil fuels with biofuels will allow emitters to sell credits. The market values of offsets and traditional products together determine land use options.
EPA 2005 GHG flux through forestry & agriculture • Forested lands sequester 12%, while agriculture emits over 6% of US emissions. • Although GHG sources and sinks in forestry and agriculture are minor portions of total emissions, they represent significant potential for offsetting projected increases in emissions.
Modeled cumulative mitigation EPA 2005 As determined by all market factors, US lands could cumulatively continue to sequester carbon throughout most of this century.
Higher values result in greater mitigation, but soils and forests for any given project become saturated at about 2025. • Beyond 2025, mitigation projects may shift to alternative practice. • Thus, constant price scenarios eventually show a declining rate of mitigation over time. • Offsets are weak in the US voluntary market, but mandatory caps in Europe rapidly drove the price to $30-40 per ton CO2Eq. Mitigation response to GHG market value
Mitigation potential through forestry and agriculture in Florida is among the highest
Reversal - loss of sequestered carbon Stored carbon can be lost Closed loop carbon
The Florida ethanol boom ? • Sources: Sugarcane, corn, sweet sorghum, citrus molasses • All have established markets; sugar prices are controlled • All sources of ethanol from carbohydrate would offset 3.5% of demand for gasoline • Mass production of cellulosic ethanol is 10 years away
Leakage • Leakage refers to GHG emissions associated with the creation and maintenance of a mitigation project • e.g., Fossil fuels used in afforestation; Fossil fuels used in production of ethanol; • Upstream and downstream effects may also cause increases in GHGs - e.g., market shift results in increased forest cutting elsewhere • Leakage GHGs decrement the offset value
Cautions about ethanol Farrell et al. Science. 2006 • Production & distribution process should be transparent & accountable through Lifecycle Analysis • Water use consequences in a state with severe water shortages
Lifecycle emissions from alternative fuels Gasoline = zero EPA 2007 This analysis is incomplete because it does not include emissions from land use changes resulting from expanded acreage for biofuel production.
Carbon debt from conversion of land to biofuel production Fargione et al. 2008
Carbon deposited at the surface is rapidly leached deeper in soil • High rainfall • Warm temperatures • Highest soil organic carbon in the coterminous US. Florida soils are a unique opportunity for carbon storage Conservation tillage = reduced or no tillage of the land = less carbon loss as emissions and runoff
Energy from livestock waste • Biogas displaces fossil natural gas. • Methane from waste represents carbon that was recently fixed through photosynthesis
Florida forests as offsets ~ 47% forested Carlton Ward 2007
Total landscape carbon uptake as determined by growth, harvest, fire, and phosphate mining. Harvest for fuel, wood products, etc. Industrial forests of the Southeast are carbon sinks Carbon budget analysis is essential for assessing mitigation potential of Florida forests. Binford et al. 2006. J Geophys Res.
Biomass supply curve for Green Cove Springs, FL At a price competitive with coal, this would supply half of the power produced by a medium size power plant. How much energy could we get from wood? Environmental concerns – Soil nutrients Matt Langholtz, UF/IFAS
Forest products • Criteria for products – • Wood products must displace products made with fossil fuels • Products must be for novel uses Cushman et al. 2007
Most environmental co-effects of mitigation through forestry can be positive • Afforestation & reforestation • High mitigation potential where no lasting snow cover • Increases forest cover • Improves water quality & watershed function • Higher biodiversity • Forest management for direct offsets - longer rotation • Enhances forest biomass & watershed function • Longer rotations provide critical habitat for animals • Fossil fuel replaced with woody biomass - short rotation • Negligible negative impact if soil nutrients are maintained • Forest Stewardship Council guidelines Indirect monetary valuation of ecosystem services
Biological Resources Water Florida Critical Lands and Waters
Additionality & baselines • Valid and marketable GHG offsets must be additional, i.e., any reductions in GHG emissions, or increases in sequestration would not have occurred without the project. • Quantifying additionality requires a valid baseline prior to initiation of the a mitigation project. • Accounting must be done with integrity - comprehensive, transparent, ongoing, and subject to independent audit. • A functional carbon market requires quantifiers, verifiers, and regulators. Harnessing Farms and Forests in the Low-Carbon Economy: How to Create, Measure, and Verify Greenhouse Gas Offsets Nicholas Institute for Environmental Policy Solutions, Zach Willey and Bill Chameides, editors. Duke University Press, June 2007.
How do you determine the baseline ? Baseline scenarios: A -No changes in land management, carbon stock does not change B -No explicit management for offsets, but carbon stock naturally increases C -Carbon stocks likely to decrease because of projected land use change
Report available at – snre.ufl.edu
Emissions offset portfolio for Florida forestry and agricultureMulkey et al. 2008 in press
Near-term carbon market value of forestry and agriculture components in FloridaMulkey et al. 2008 • $678 million annually @ $40 Mg-1 CO2eq
Additional annual value from traditional marketsMulkey et al. 2008 • Biogas as replacement for fossil natural gas - $62.7 million • Sale of crop and logging residues as fuel - $48 million • Reduced fuel costs from conservation tillage - $14 million Total annual value of portfolio at $20 Mg-1 CO2eq~ $ 465 million
Land & ocean have been carbon sinks • Carbon Stocks –can be managed for • reducing loss • increased sequestration
2 oC Warming and land use change are synergistic
Land use change in Florida Land use change generally results in loss of carbon stocks Pielke, R. A. Science. 2005
Land use change is one cause of regional climate change California land use amplifies warming • Warming - • - 50% due to global warming • - 50% due to land use change • Large urban areas warmed 2-5 times more than the state mean 1950-2000. Heterogeneous “forcing” of regional climate LaDochy et al. 2007. IJC.
Land use impacts on south Florida climate Maximum temperature Precipitation Minimum temperature Minimum temperatures are lower due to loss of wetlands. Marshall et al. 2005. Monthly weather review.; Pielke, RA, Sr.et al. 2007. Ag For Met. Marshall et al. Nature 2003
Consistent with present trends, the Southeast will warm less than the rest of the US. North Florida will warm more than south Florida. Precipitation will decrease in south Florida, but remain approximately constant in north Florida
With positive feedback from the carbon cycle, mitigation must be even more aggressive Friedlingstein, Nature 2008 Conclusion: Management of landscape carbon stocks is not optional.
Landscape based mitigation options are rapidly disappearing 2015-2020
Science that changed our understanding of our place in nature