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Transcript of 15 July 2010 Baseline time accounting CARB expert workgroup meeting Time accounting subgroup –...
15 July 2010
Baseline time accounting
CARB expert workgroup meetingTime accounting subgroup – Interim report
Jesper Hedal Kløverpris, PhD – NovozymesSteffen Mueller, PhD – University of Illinois
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The four main steps
Determine -
1.…amount of land affected (in relation to baseline)
2.…types of land affected (grassland, forest etc.)
3.…carbon stocks/sequestration of land affected
4.…how to deal with time accounting
Although the ‘land use baseline’ is usually considered
in step 1, it is most often not considered in step 4.
Estimating GHG emissions from ILUC
Current time accounting approach
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ILUC contribution based on 30 year production period:
30 g CO2e/MJ
Source: CARB (2009), Fig. C4-3
Result dependent on assumed biofuels production period
What would have happened to this land in the baseline?
Baseline land use change
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Source: Bruinsma (2009), Fig. 6
Developing world: Arable land use mainly increasing
Developed world: Arable land use mainly decreasing
Arable land and land under permanent crops (only food and feed)
Accelerated expansion
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Baseline
Human land use
Biofuels scenario (1 y prod.)
Human land use
Land for biofuelYear 1
Year 0
Year 2
Baseline
Human land use
Biofuels scenario (2 y prod.)
Human land use
Land for biofuelYear 1
Year 0
Year 2
The figures on this slides are for illustrative purposes only and do not indicate any sizes or proportions of indirect land use change
ILUC taking place in a region where land use is already expanding (baseline)
Delayed reversion
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Baseline
Human land use
Biofuels scenario (1 y prod.)
Human land use
Land for biofuelYear 1
Year 2
Year 0
Baseline Biofuels scenario (2 y prod.)
The figures on this slides are for illustrative purposes only and do not indicate any sizes or proportions of indirect land use change
ILUC taking place in a region where land use is ‘contracting’ (baseline)
Human land use Human land use
Land for biofuelYear 1
Year 2
Year 0
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Cum
ula
tive G
HG
em
issi
on
s (g
CO
2e)
Time (y)
Baseline implications for time accounting
Baseline
Baseline
One year
ILUC: Accelerated expansion
ILUC: Delayed reversion
Regional baseline: Expansion of land use
Regional baseline: Contraction of land use
Direct (avoided) fossil emissions
Direct ethanol emissions
No GHG decay assumed above – graphs for illustrative purposes only and not meant to indicate proportions of GHG emissions
Areas indicated equivalent to ton·years of carbon
TA
Analytical time
horizon
Saved
Ind
uced
Land use projections literature review
Current trends in agricultural land use (sources)
Developing world
Cropland area expanding, forest area decreasing
Developed world
Cropland area contracting, forest area increasing
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Sources: FAOSTAT (2010) and Global Forest Resources Assessment 2010 – Key findings (FAO 2010)
Land use projections literature review
Future trends in agricultural land use (references)
Climate change and agricultural vulnerability(Fischer et al. 2002)
World Agriculture Towards 2015/2030 (Bruinsma 2003)
The resource Outlook to 2050 (Bruinsma 2009)
World Food and Agriculture to 2030/50 (Fischer 2009)
Millennium Ecosystem Assessment (Alder et al. 2005)
Climate benefits of changing diet (Stehfest et al. 2009)
Background report to the OECD Environmental Outlook to 2030 (Bakkes et al. 2008)
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Full references given at the end of the slideshow
Land use projections literature review
The studies mentioned on the previous slide differ in several aspects such as temporal scope, yield assumptions, modeling framework, land use type(s) considered, regional disaggregation, drivers etc.
The studies come out with different results but all of them predict a steady increase in global agricultural land use up to 2030 and, except for Stehfest et al. (2009); this increase is expected to continue until 2050
The conditions for ’baseline time accounting’ thereby seem to be in place for decades ahead
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Converting ‘accelerated expansion’ and ‘delayed reversion’ into a GWP(100)
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Following the definition of the GWP(100):
Take the cumulative radiative forcing (CRF) during 100 years caused by the emissions from the land conversion taking place as an indirect effect of biofuels production
Take the CRF within the same period of time for the same land area but for the emissions that would have occurred in the baseline (a shift in emissions by one year)
Divide the difference in CRF between these two situations by the CRF of a pulse emission of one unit of CO2 seen over 100 years
This procedure will result in an ILUC factor equivalent to the GWP(100) – consistent with the unit used for direct emissions
Preliminary results
”30 year method”Baseline time
accounting
BTIME numbers1 30 g CO2e/MJ 10 g CO2e/MJ
Searchinger et al. (2008)2 104 g CO2e/MJ 23 g CO2e/MJ
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1 GTAP-WH, only accelerated expansion assumed (no regional disaggregation)2 Only accelerated expansion assumed
The preliminary results have been derived by use of a climate model kindly made available by Martin Persson, University of Gothenburg, Sweden. Additional refinement of data input and quality control is still required.
Conclusions
The ILUC factor must be consistent with direct emissions
Under current and near term baseline conditions, indirect land use change (ILUC) will likely be constituted by
Accelerated expansion (typical for the developing world)
Delayed reversion (typical for the developed world)
Under those conditions, assumptions about the biofuels production period are unnecessary – however:
If a 30 year biofuels program is considered, projections of the land use baseline 30 years into the future is required
Global agricultural land use is expected to increase at least to 2030 and most likely also to 2050
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Conclusions (continued, input from K. Kline)
Interacting with baseline conditions, the ILUC could also be constituted by use of previously cleared lands and -
Reduced fire and avoided (decreased) expansion (developing world)
Avoided reversion to urban/commercial/industrial and other uses that (in absence of ILUC) is representing loss of productive capacity and carbon carrying capacity (developed world)
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Thank you
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Extra slides and references
Graphs for discussion
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Baseline
Biofuels
Acc. exp.: Accelerated expansion
Del. rev.: Delayed reversion
Legend
Acc. exp. Del. rev.
Ha
Time
Acc. exp. Del. rev.
Additional expansionHa
Time
Del. rev.Acc. exp.
Ha Additional expansion
Time
Hertel et al. (2010)
Not straight forward to apply ’baseline time accounting’ to this study because it has partly been considered already:
‘It may be […] that technological change will increase maize yields so much […] that total maize acreage actually falls, but our analysis is directed (in that case) to how much more it would fall without the biofuel increase.’
In Europe, we use a lower emission factor for deforestation because cropland is already reverting to forest and biofuel cropland demand merely slows this process. The result is avoided [slow] sequestration rather than [rapid] release of aboveground carbon.
Baseline not considered in time accounting
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Delayed reversion!
Delayed reversion
Land quality (Kløverpris et al. 2010)
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Sustainable development and time accounting
In 1987, The Brundtland Commission defined sustainable development as:
…development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
Do we only care about the next 30 years?
GWP values for CO2, CH4, and N2O
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20 years 100 years 500 years
CO2 1 1 1
CH4 72 25 8
N2O 289 298 153
Source: IPCC’s Fourth Assessment Report
References Alder et al. (2005): Changes in Ecosystem Services and Their Drivers across the Scenarios. Chapter 9 in: Carpenter
SR, Pingali PL, Bennett EM, Zurek MB (eds) (2005): Ecosystems and Human Well-being: Scenarios, Volume 2. 2005 Millennium Ecosystem Assessment, Island Press, Washington·Covelo·London
Bakkes et al. (2008): Background report to the OECD environmental outlook to 2030. Overviews, details, and methodology of model-based analysis. MNP Report 500113001/ 2008, ISBN 978-90-6960-196-0, available at www.pbl.nl/en
Bruinsma J (ed) (2003): World Agriculture: towards 2015/2030. An FAO Perspective. FAO, Earthscan, London
Bruinsma J (2009): The resource Outlook to 2050. By how much do land, water and crop yields need to increase by 2050?, FAO Expert meeting on how to feed the world in 2050, 24-26 June 2009.
CARB (2009): Proposed Regulation to Implement the Low Carbon Fuel Standard – Vol. 1, California EPA
FAO (2010): Global Forest Resources Assessment 2010 – Key findings. Food and Agriculture Organization of the United Nations, Rome, available at www.fao.org/forestry/fra2010
FAOSTAT (2010): http://faostat.fao.org, United Nations Food and Agricultural Organisation
Fischer G, Shah M, van Velthuizen H (2002): Climate Change and Agricultural Vulnerability, IIASA, Remaprint, Vienna
Fischer (2009): World Food and Agriculture to 2030/50: How do climate change and bioenergy alter the long-term outlook for food, agriculture and resource availability? FAO Expert meeting on how to feed the world in 2050, 24-26 June 2009.
Hertel TW, Golub AA, Jones AD, O’Hare M, Plevin RJ, Kammen DM (2010): Global Land Use and Greenhouse Gas Emissions Impacts of U.S. Maize Ethanol: Estimating Market-Mediated Responses, BioScience 60 (3) 223-231
Kløverpris JH, Baltzer K, Nielsen PH (2010): Life cycle inventory modelling of land use induced by crop consumption Part 2: Example of wheat consumption in Brazil, China, Denmark and the USA, International Journal of Life Cycle Assessment 15:90-103
Searchinger et al. (2008): Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land Use Change, Science 319: 1238–1240
Stehfest E, Bouwman L, van Vuuren DP, den Elzen MGJ, Eickhout B, Kabat P (2009): Climate benefits of changing diet. Climatic Change 95:83–102
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