GHG Emissions and Mitigation
Potentials in Agriculture
Tomoko HASEGAWA
Graduate school of Engineering, Kyoto University
15,16 February,2009,
11th AIM International Workshop
National Institute for Environmental Studies, Tsukuba, Japan

Contribution Ratio to Global Warming• Agriculture accounts for ...
– 14% of total GHG emission.
– 50% of total CH4 emission and 60% of N2O emission in2005 (IPCC, 2007).
Agriculture

residential alandcommercial agriculture
8%14%transport
13%
energysupply26%

N2O
8%
CH414%

deforestatio
n 17%
industry
19%

F-gases1%

CO2(deforestation, etc)
waste and17%
wastewater
CO2(other)
3%
2.8%

contribution ratio by Sector

CO2 fossil
fuel use
57%

contribution ratio by Gas

スライド 2ｈ3

単位を，MtCO2eqに！
長谷川 知子, 2008/01/27

Objectives(1) To estimate and evaluate global GHG emissions andreduction potentials in Agriculture(2) To specify effective technologies, regions and emission
sources with high reduction potentials
To evaluate GHG emissions and reduction potentials,
we need to integrate the relating events such as…
economicdevelopment
population
growthGHGemission

changing
food needs
agricultural
productionGHG reduction
technology

climatechangeproduction
efficiency
technicalinnovation

Methodology• Model is used for estimation.
World regions
Future population
scenario

Future economic
scenario

Exogenous
variables

Agriculture Trade Model

Enduse Model

GHG emissions
Reduction Potentials

Bottom-up

determines combination and stocks ofGHG reduction technologies

Top-down

Productionof agricultural commodities

Agricultural Trade Model (ATM)• Structure: Partial equilibrium model
1200 functions and equations• Input: Population and GDP• Output: Production of agricultural commodities• Calibration term: 1971 - 2003
• Estimation term: 2004 - 2030
• Region: 23 world regions

Structure
23 world regions

World price
Shipping cost
Consumer subsidy

PopulationGDP

Tax and tariff
Intermediate priceConsumer price

Producer subsidy

Producer price

StocksDomestic Market
PConsumption

Q0Production

Net trade

P0Q

World Market

Exogenous
variable

Endogenous
variableStructure
World price

23 world regions

Shipping cost
Consumer subsidy

PopulationGDP

Tax and tariff
Intermediate priceConsumer price

Producer subsidy

Producer price

StocksDomestic Market
PConsumption

Q0World price is decided
in order to take balancein the world.

Production23 world regions
are connected
through world market.

Net trade

P0Q

World Market

Exogenous
variable

Endogenous
variableStructure
23 world regions

World priceTax and tariff

Shipping cost
Consumer subsidy

Population

GDP

Intermediate priceConsumer price

Stocks

Producer priceDomestic Market

Consumer price
P andConsumption producer price are0 price.
related to world

Producer subsidy

Q

Policies, tax and tariff aregiven exogenously.
Production

Net trade

P0Q

World Market

Exogenous
variable

Endogenous
variableStructure
23 world regions

World price
Shipping cost
Consumer subsidy

PopulationGDP

Tax and tariff
Intermediate priceConsumer price

Producer subsidy

Producer price

StocksPConsumption

Q0

Consumptionfunction

Production

Production
function

Net trade

P0Q

World Market

Exogenous
variable

Endogenous
variable

Functions: Production and Consumption• Production function
Productioni , r ,tf ( Productioni , r ,t 1 , Producer Price j , r ,t )• Consumption (Con.) function
Food Con.i , r ,tf ( Consumer pricei , r ,t , GDPcapr ,t , Populationr ,t )Feed Con.i , r ,tf ( Consumer pricei , r ,t , Livestock productioni ,r ,t )• Import and export are also decided by prices.

Structure
23 world regions

World price
Shipping cost
Consumer subsidy

Population

GDPTax and tariff
Intermediate priceConsumer price

Producer subsidy

Producer price

StocksDomestic Market
PConsumption

Q0Production, consumption
and trade are calculated
to take balance in one
region.

Production

Net trade

P0Q

World Market

Exogenous
variable

Endogenous
variableBalance Equations• Domestic balance equation

Productioni , r ,tImporti , r ,tConsumptioni , r ,tExporti , r ,t

• World balance equation

Exporti , r ,trImporti ,r ,trStocki , r ,tMethodology• Model is used for estimation.
world regions
Future population
scenario

Future economic
scenario

Exogenousvariables

Agriculture Trade Model

Enduse Model

GHG emissions
Reduction Potentials

Bottom-up

decides combination and stocks ofGHG reduction technologies

Top-down

Productionof agricultural commodities

Enduse Model••••

Structure: Dynamic model
Input: Agricultural production
Outputs: GHG emissions and Reduction potentials
Calculates combination and stocks of GHG reduction technologies
in order to minimize total reduction cost.
23 world regions

Production

Croplands

Livestock animals

Technology 1
Technology 2Technology 3

Technology 4
Technology 5
Technology 6

Technology Database

GHG emissions/Reduction
potentials
Reduction Cost
→ Minimum

Technology Stock Change
A number of technology (tech. ) is changed by 1) exchangeand 2) introduction.
Stock (T)=Stock(T-1) – ①exchanged tech.(T) + ②Introduced tech.(T)The number of livestock animal, orThe area of croplands② Introduced Technology①Exchange････
Tech1

2000 ･･･ T-1

Tech1

Technology stocks

Tech2

Technology change iscalculated in order tominimize total
reduction cost.

T ･･･ 2030 [year]

Application

Objective• 23 world regions• 2000-2030• Population: medium estimates of UN(2006)• GDP: Akashi (2009)
Gases

Emission SourcesEnteric fermentation

CH4

Manure management

CH4, N2O

Cropland and Soils

N2O

Rice paddy

CH4, N2O

Baseline Emission in 2000-2030

5591MtCO2eq

1.4 times

Cropland and Soils N2O
Rice paddy CH4
Manure management N2O
Manure management CH4
Enteric fermentation CH4

40%

2030

2025

2020

2015

2010

30%
2005

6000
5000
4000
3000
2000
1000
03959MtCO2eq

2000[MtCO2eq]

CH4+N2O Emission• World GHG emission will increase by 1.4 times by 2030.
• In 2030,emissions from croplands and livestock entericfermentation account for 40% and 30% of it respectively.
• Emission from livestocks will increase at high growth rate.ｈ2• Emission from rice paddy will decrease.

スライド 18ｈ2

C:¥GAMS¥Emission Model vol2¥output¥ReducionPotential
長谷川 知子, 2008/08/14

GHG Emission in 2000, 2030
• GHG Emission of this study is middle of other estimates.
• Cropland and Soils and Enteric Fermentations occupy
high contribution ratio.
in 2000

in 2030

6000

Rice paddy CH4
Cropland and Soils N2O
Manure management N2O
Manure management CH4
Enteric fermentation CH4

4000
2000

BCFAOIMAGE2.1

This study
USEPA
ABCFAO0This study
USEPAAGHG Emission[MtCO2eq] .

8000

IMAGE2.1

Which is Effective Source?
In 2030 Reduction Potential by Source• In 2030, total max. reduction potential is 1403 Mt CO2eq.
• Technologies for rice paddy is good.
• Technologies for enteric fermentation is not good.
Reduction Potentials [MtCO2eq]
Marginal Abatement Cost [US$/tCO2eq]
Emission sources
<0<20
<50
<100>100
Enteric fermentation CH4000
41255
3255
Manure management CH4095
98110345
Manure management N2O0565762205Rice paddy CH40367
198
716

381
381
198
737

381
198
793

381
381
217
1403

Cropland and Soils N2OTotal

148
148

35% of total GHG emission from agriculture in 2000.

Where is Effective Region?
In 2030 Reduction Potential by region• Reduction Potential in China, India and USA is large.
• Measurements in there regions take comparative low costs.
other developing
transition countries
IndiaChina
other developedUSAEU15Japan

Marginal
reduction cost
[US$/tCO2eq]<00-2020-50
50-100>100

0 100 200 300 400 500 600
GHG reduction potentials [MtCO2eq]

What is Effective Technology ?
Sub-optimal fertilizer application
Reduce fertilization to 90%
Reduce fertilization to 80%
Reduce fertilization to 70%
Split fertilization
Convert fertilizational tillage to no-till
Nitrogen inhibitor
Optimize distribution geometry
Fertilizer Free Zone
Spreader maintenance
Alternative flooding/Drainage
Direct Wet Seeding
Rice Straw Compost
Addition of Phosphogypsum
Upland rice
Shallow flooding
Off-season straw
Midseason drainage
Ammonium sulfate
Propionate precursors
Pribiotics
Slowing down anaerobic decomposition
Daily spread of manure
Covered lagoon
Anaerobic Digestion -Farmscale plant
Anaerobic Digestion -Centralised plantMarginal Abatement Cost
[US$/tCO2eq]

Not good<0<20<50<100>100

Good but expensive
The highest
economic efficiency

0204060
80
100
Average annual reduction potentials [MtCO 2eq/yr]

Conclusion
We introduced a model to estimate GHG emissions andreduction potentials in agriculture. We showed you anapplication to estimate and specify effective technologies,
high reduction potential regions and emission sources.
•••••

Total non-CO2 emission from agriculture is about 3959
MtCO2eq in 2000.
Major emission source is Cropland and Soils．
In 2030, the maximum global reduction potential isexpected to be 1403 MtCO2eq(35% of emission in 2000).
China and India have major reduction potentials.
The reduction technology with most economicallyefficient is expected to be "daily spread of manure ".

Thank you for your attention