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Joint GCAM Community Modeling Meeting and GTSP Technical Workshop Joint Global Change Research Institute College Park, Maryland, USA Overview of the Global Change Assessment Model (GCAM) THE JGCRI GCAM TEAM Thursday, October 13, 2016 PNNL-SA-90713

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Page 1: Overview of the Global Change Assessment Model (GCAM) · PDF fileOverview of the Global Change Assessment Model (GCAM) ... General Characteristics of High-Resolution, ... draw from

Joint GCAM Community Modeling Meeting and GTSP Technical Workshop Joint Global Change Research Institute College Park, Maryland, USA

Overview of the Global Change Assessment Model (GCAM) THE JGCRI GCAM TEAM

Thursday, October 13, 2016

PNNL-SA-90713

Page 2: Overview of the Global Change Assessment Model (GCAM) · PDF fileOverview of the Global Change Assessment Model (GCAM) ... General Characteristics of High-Resolution, ... draw from

Outline

! Brief introduction to Integrated Assessment Models

! Overview of GCAM

! Detailed information on GCAM’s ! Socioeconomics, ! Energy, ! Agriculture and land use, ! Policies, ! Emissions ! Climate

! Discussion

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INTRODUCTION TO IA MODELS

3

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What is an Integrated Assessment (IA) Model?

IAMs integrate representations of multiple human and natural Earth systems. ! IAMs provide insights that

would be otherwise unavailable from disciplinary research.

! IAMs capture interactions between complex and highly nonlinear systems.

! IAMs provide natural science researchers with information about human systems such as GHG emissions, land use and land cover.

! IAMs support national, international, regional, and private-sector decisions.

Human Systems

Natural Earth Systems

ENERGY

Economy Security

Settlements

Food

Health

Managed Ecosystems

TechnologyScience

TransportPopulation

Sea Ice Carbon Cycle

Earth System Models

EcosystemsOceans

Atmospheric Chemistry

Hydrology

Coastal Zones

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The Global Change Assessment Model (GCAM) is a “High-Resolution” IA Model

Model Home Institution AIM

Asia Integrated Model National Institutes for

Environmental Studies, Tsukuba Japan

GCAM Global Change Assessment Model

Joint Global Change Research Institute, PNNL, College Park, MD

IGSM Integrated Global System Model

Joint Program, MIT, Cambridge, MA

IMAGE The Integrated Model to Assess the Global Environment

PBL Netherlands Environmental Assessment Agency, Bildhoven,

The Netherlands

MESSAGE Model for Energy Supply Strategy Alternatives and their General

Environmental Impact

International Institute for Applied Systems Analysis; Laxenburg,

Austria

REMIND Regionalized Model of Investments and Technological

Development

Potsdam Institute for Climate Impacts Research; Potsdam,

Germany

High-Resolution Models and Modeling Teams

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General Characteristics of High-Resolution, Global IA models

! High-resolution, global IA models are: ! Global in scope, ! Include representations of energy and agricultural/land use systems ! Include all anthropogenic sources of emissions, ! Include some representation of the climate system.

! However, there is significant variation across models as to their: ! Spatial resolution ! Inclusion of gases and substances ! Energy system detail ! Representation of agriculture and land-use ! Economic assumptions ! Degree of foresight ! Sophistication of the climate model component ! Degree of integration of model components

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Integrated Assessment Research and Model Development is Problem Driven

1980’s Projections of emissions and

concentrations Comparison of Emissions Trajectories Consistent With Various Atmospheric

CO2 Concentrations Developed by the IPCC (S350-S750) and by Wigley, Richels, and Edmonds (S350a-S750a)

-2

0

2

4

6

8

10

12

14

16

1990 2015 2040 2065 2090 2115 2140 2165 2190 2215 2240 2265 2290

PgC

/yr

S350

S450

S550

S650

S750

WRE 350

WRE 450

WRE 550

WRE 650

WRE 750

energy-economy-climate

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Integrated Assessment Research and Model Development is Problem Driven

Energy Supply

Carbon Prices

Energy, Technology, and Mitigation

Value of Technology

1990’s through 2000’s

$0

$100

$200

$300

$400

$500

$600

$700

$800

$900

$1,000

2020 2040 2060 2080 2100

Inde

x (y

r 20

00 =

1)

MINICAM_Level1

MINICAM_Level2

MINICAM_Level3

MINICAM_Level4 Cumulative Carbon Emissions and Cumulative

Compliance Cost across Scenarios

$0

$2

$4

$6

$8

$10

$12

$14

450 ppmv 550 ppmv 650 ppmv 750 ppmv

Cum

ulat

ive

Glo

bal C

ompl

ianc

e C

ost

(Tril

lion

U.S

. 200

0$, 5

% D

isco

unt R

ate)

0

200

400

600

800

1,000

1,200

1,400

Cum

ulat

ive

Car

bon

Em

issi

ons

(GTC

)

All Advances

Reference Technology

Cumulative Emissions

Advanced Technology

ENERGY-ECONOMY-climate 1980’s Projections of emissions

and concentrations Comparison of Emissions Trajectories Consistent With Various Atmospheric CO2 Concentrations Developed by the IPCC (S350-S750) and by Wigley,

Richels, and Edmonds (S350a-S750a)

-2

0

2

4

6

8

10

12

14

16

1990 2015 2040 2065 2090 2115 2140 2165 2190 2215 2240 2265 2290

PgC

/yr

S350

S450

S550

S650

S750

WRE 350

WRE 450

WRE 550

WRE 650

WRE 750

Energy Systems

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Integrated Assessment Research and Model Development is Problem Driven

ENERGY-ECONOMY-land-climate

2000’s Mitigation and land use

-3

-2

-1

0

1

2

3

4

5

6

7

8

2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100

GtCO

2/yr

LowAgProductivityGrowth

ReferenceAgProductivityGrowth

HighAgProductivityGrowth Crop production and land use

changes

1980’s Projections of emissions

and concentrations Comparison of Emissions Trajectories Consistent With Various Atmospheric CO2 Concentrations Developed by the IPCC (S350-S750) and by Wigley,

Richels, and Edmonds (S350a-S750a)

-2

0

2

4

6

8

10

12

14

16

1990 2015 2040 2065 2090 2115 2140 2165 2190 2215 2240 2265 2290

PgC

/yr

S350

S450

S550

S650

S750

WRE 350

WRE 450

WRE 550

WRE 650

WRE 750

Energy, Technology, and Mitigation

1990’s through 2000’s Land Use Change

Emissions

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Integrated Assessment Research and Model Development is Problem Driven

1980’s Projections of emissions and concentrations

Comparison of Emissions Trajectories Consistent With Various Atmospheric CO2 Concentrations Developed by the IPCC (S350-S750) and by Wigley,

Richels, and Edmonds (S350a-S750a)

-2

0

2

4

6

8

10

12

14

16

1990 2015 2040 2065 2090 2115 2140 2165 2190 2215 2240 2265 2290

PgC

/yr

S350

S450

S550

S650

S750

WRE 350

WRE 450

WRE 550

WRE 650

WRE 750

Energy, Technology, and Mitigation

1990’s through 2000’s

2000’s Mitigation and land use

TODAY

????

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Examples of Current Questions for the IA Community

! Type 1: Where are the NDCs taking us? How to implement and ramp up action? What’s actually realistic for different countries?

! Type 2: How will these mitigation activities link to the other societal goals (e.g., SDGs)? Will they be limited by energy-water-land constraints?

! Type 3: How can we plan investments and strategy taking into account climate impacts and a broad range of additional stressors and dynamics?

! Type 4: Where are the biggest future climate-related national security risks, domestically and internationally?

! Can you help us interpret and understand this stuff? What’s the confidence in any of this?

Incorporating climate impacts, adaptation, and

vulnerability

Increased “realism”,

particularly with regards to regional

dynamics

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GCAM has a long history…

! GCAM was one of four models chosen to create the representative concentration pathways (RCPs) for the IPCC’s AR5.

! GCAM was one of six models chosen to create the shared socioeconomic pathways (SSPs).

! GCAM was one of three models used to create scenarios for Climate Change Science Program (CCSP).

! GCAM was a prominent tool for analysis in the Climate Change Technology Program (CCTP).

! GCAM has participated in virtually every major climate/energy/economics assessment over the last 20 years: ! Every EMF study on climate ! Every IPCC assessment

! GCAM has been used for strategic planning by energy and other private companies.

! GCAM is now used by research institutions and governments internationally.

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The Global Change Assessment Model

! GCAM is a global integrated assessment model ! GCAM links Economic, Energy, Land-use, Water, and Climate systems

! Runs in 5-year time-steps. ! Meant to analyze consequences of

policy actions and interdependencies ! GCAM is a community model ! Documentation available at:

wiki.umd.edu/gcam ! Used to evaluate impacts of

these threads: ! Socioeconomic

development ! Climate mitigation and

impacts ! Technology and

resource developments ! Energy policies

283 Land Regions

32 Energy Economy Regions

233 Water Basins

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Scenario Assumption

s

Policies

Technology Characteristics

Labor Productivity

Population

Model Equations, Relationships,

and Parameters

Modeled Scenario

Concentrations and Temperature

Land Use

Agricultural Production

Energy Supplies and Demands

Prices

Emissions

Policies

Technology Characteristics

Labor Productivity

Population

What do IA Models do?

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What is GCAM?

15

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What is GCAM?

! What does it do? ! How does it work? ! What kinds of questions can it answer? ! What’s new in this release?

16

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What is GCAM?

283 Land Regions

32 Energy Economy Regions

235 Water Basins

! GCAMisaglobalintegratedassessmentmodel! GCAMlinksEconomic,Energy,Land-use,Water,andClimatesystems

! Runsin5-year9me-steps.! Meanttoanalyzeconsequencesof

policyac9onsandinterdependencies! GCAMisanopen-source

communitymodel! Documenta9onavailableat:

wiki.umd.edu/gcam! Usedtoevaluateimpactsofthese

threads:! Socioeconomic

development! Climatetreatycompliance! Technologyandresource

developments! Energypolicies

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What’s inside GCAM?

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The Solver Algorithm

! Start with a vector of initial guess prices ! The main body of GCAM calculates demand disequilibrium

! This part can be run multithreaded. ! Solve:

! Broyden’s method solver. ! Numerous heuristics to improve solver convergence. ! Iteration step can be calculated either with LU decomposition or SVD (use

the latter if you can). ! Result:

! Equilibrium prices ! Quantities, market shares, land use, resource depletion, etc.

!P !

E(!P)

!E(!P) = 0

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Frequently Asked Questions

! Common question: ! Does GCAM include foresight?

! Answer: ! For long-term investment

decisions, we assume that decision-makers think about the future. That is, they may consider the costs and profits over the full lifetime of an electricity generation unit before building.

! However, we are myopic in that we uses current prices when making these decisions.

! Decision-makers do not know future prices! Source: Calvin et al. (2014). The EU20-20-20 Energy Policy

as a Model for Global Climate Mitigation. Climate Policy.

Land Use Change Emissions Leakage

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Frequently Asked Questions

! Common question: ! Does GCAM optimize?

! Answer: ! Not exactly. ! GCAM is a market equilibrium model, so it adjusts prices until supplies

and demands are equal. ! However, GCAM assumes that producers maximize profit and

consumers minimize cost. ! And, under certain conditions, welfare economics tells us that market

equilibria are (Pareto) optimal. ! GCAM is not intertemporally optimizing.

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! Prices and production quantities: ! Energy sectors ! Transportation ! Primary energy resources ! Agricultural products

! Land use ! Crops (by type) ! Pasture ! Unmanaged

! Water demand ! Raw demand by sector ! Response to scarcity

! Greenhouse gases ! Economic cost of policies

! Economic loss ! Income transfer

Car

bon

Pric

e

What can you do with GCAM?

22

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Deep Regional Dives in GCAM

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What’s new in GCAM?

! Hector is now the default climate model. ! Near-term population and GDP adjusted to match IMF projections for

all included scenarios. ! Users can now configure GCAM to save only the results they plan to

use. ! Updates to electricity and liquid fuel sector costs, reflecting recent

literature. ! Various performance (i.e., speed) enhancements. ! Various minor bug fixes.

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THE MACRO-ECONOMY IN GCAM

2016

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Core GCAM structure: The Macro-economy

26

WATER

►  Energy ►  Agriculture ►  Domestic

Water Demand

►  Surface ►  Ground ►  Natural Lakes

Water Supply ►  Water prices

Water Markets

Land Characteristics

Climate Inputs

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The Macro-economy in the present release version

! 𝐺𝐷𝑃↓𝑟,𝑡+1 = 𝑃𝑂𝑃↓𝑟,𝑡+1 (1+𝐺𝑅𝑂↓𝑟,𝑡 )↑𝑡𝑆𝑡𝑒𝑝 ( 𝐺𝐷𝑃↓𝑟,𝑡  /𝑃𝑂𝑃↓𝑟,𝑡  ) 𝑃↓𝑟,𝑡+1↑𝛼 

! r=region, t=time period ! POP=population, ! GRO=rate of growth of per capita income ! P=aggregate price of energy service ! α=GDP feedback elasticity

! Note that the GDP feedback elasticity is set to zero in default mode.

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GCAM 4.3 is moving to SSP2 population and GDP

!  Middle of the Road scenario from Shared Socioeconomic Pathways:

!  O’Neill et al. Climatic Change (2014) 122: 387.

!  Near-term GDP growth is adjusted to reflect economic stagnation in several countries.

!  Current release does not include other SSP assumptions beyond population and GDP.

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Population and GDP 2… 2… 2… 2… 2… 2… 2… 2… 2… 2…

USA EU-12 EU-15 EuropeanFreeTradeAssociation Australia_NZCanada Japan China India Africa_EasternAfrica_Northern Africa_Southern Africa_Western SouthAfrica IndonesiaPakistan SouthKorea Taiwan CentralAsia SouthAsiaSoutheastAsia Argentina Brazil Colombia MexicoCentralAmericaandCaribbean SouthAmerica_Northern SouthAmerica_Southern Russia Europe_EasternEurope_Non_EU MiddleEast

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ENERGY

30

Page 31: Overview of the Global Change Assessment Model (GCAM) · PDF fileOverview of the Global Change Assessment Model (GCAM) ... General Characteristics of High-Resolution, ... draw from

The Global Change Assessment Model

Page 32: Overview of the Global Change Assessment Model (GCAM) · PDF fileOverview of the Global Change Assessment Model (GCAM) ... General Characteristics of High-Resolution, ... draw from

The Energy System: Structure

Oil Production

Bioenergy Conversion

Electric Power

Generation

Liquids Refining

Hydrogen

N. Gas Production

Coal Production

Bioenergy Production

Gas Processing

Nuclear

Hydro

Solar

Liquids Market

Bioenergy Market

Natural Gas Market

Hydrogen Market

Electricity Market

Wind

Geothermal

Buildings Sector

Industrial Sector

Transport Sector

Coal Market

Uranium

Resource Production Energy Transformation End-Use Final Energy Carriers

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The Energy System: Resources

! Resources serve as inputs to conversion technologies to produce energy carriers such as electricity, liquid fuels, and hydrogen. ! For example, several types of solar technologies – CSP, central PV,

rooftop PV – draw from the solar resource to produce electricity. ! Exhaustible Resources in GCAM

! Coal ! Natural Gas ! Oil (conventional and unconventional) ! Uranium

! Renewable Resources in GCAM ! Solar ! Wind (onshore and offshore combined into one) ! Geothermal ! Bioenergy (several forms)

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The Energy System: Resources: Conventional Oil

!   Oil, Gas, and Coal Resources derived from Rogner 1997 (per the GCAM wiki), but please refer to that source for original data.

!   Note: there is an additional 90 ZJ of unconventional oil in GCAM 4

0

2

4

6

8

10

12

14

0 5 10 15 20 25

2010$/G

J

ZetaJoules

GlobalConven5onalOilSupply

0

1

2

3

4

5

6

7

USA

Africa_Eastern

Africa_Northern

Africa_Southe

rn

Africa_Western

Australia_N

ZBrazil

Canada

Cent.A

mericaandCar.

CentralA

sia

China

EU-12

EU-15

Europe

_Eastern

Europe

_Non

_EU

Europe

anFreeTradeAss.

India

Indo

nesia

Japan

Mexico

MiddleEast

Pakistan

Russia

SouthAfrica

SouthAm

erica_Northern

SouthAm

erica_Southe

rn

SouthAsia

SouthKo

rea

Southe

astA

sia

Taiwan

ArgenT

na

Colombia

ZetaJoules

RegionalConven5onalOilSupply

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The Energy System: Resources: Natural Gas

!   Oil, Gas, and Coal Resources derived from Rogner 1997; please refer to that source for original data.

!   Note: The highest cost grade of natural gas is not shown here. We have ~200 ZJ more natural gas available in the model (hydrates).

0

2

4

6

8

10

12

14

0 5 10 15 20 25 30 35 40

2010$/G

J

ZetaJoules

GlobalNaturalGasSupply

0

1

2

3

4

5

6

USA

Africa_Eastern

Africa_Northern

Africa_Southe

rn

Africa_Western

Australia_N

ZBrazil

Canada

Cent.A

mericaandCar.

CentralA

sia

China

EU-12

EU-15

Europe

_Eastern

Europe

_Non

_EU

Europe

anFreeTradeAss.

India

Indo

nesia

Japan

Mexico

MiddleEast

Pakistan

Russia

SouthAfrica

SouthAm

erica_Northern

SouthAm

erica_Southe

rn

SouthAsia

SouthKo

rea

Southe

astA

sia

Taiwan

ArgenS

na

Colombia

ZetaJoules

RegionalNaturalGasSupply

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The Energy System: Resources: Coal

!   Typically use around 30 ZJ to 2100 – so very flat part of curve !   Total Resources in GCAM extend to over 250 ZJ at higher

costs

0

10

20

30

40

50

60

70

80

USA

Africa_Eastern

Africa_Northern

Africa_Southe

rn

Africa_Western

Australia_N

ZBrazil

Canada

Cent.A

mericaandCar.

CentralA

sia

China

EU-12

EU-15

Europe

_Eastern

Europe

_Non

_EU

Europe

anFreeTradeAss.

India

Indo

nesia

Japan

Mexico

MiddleEast

Pakistan

Russia

SouthAfrica

SouthAm

erica_Northern

SouthAm

erica_Southe

rn

SouthAsia

SouthKo

rea

Southe

astA

sia

Taiwan

ArgenT

na

Colombia

ZetaJoules

RegionalCoalSupply

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

0 10 20 30 40 50

2010$/G

J

ZetaJoules

GlobalCoalSupply-Truncated

Page 37: Overview of the Global Change Assessment Model (GCAM) · PDF fileOverview of the Global Change Assessment Model (GCAM) ... General Characteristics of High-Resolution, ... draw from

The Energy System: Renewable Resources

!   In GCAM the capacity factors of wind turbines are based on detailed global supply curves [1, 2]. Similarly, the capacity factors of photovoltaic panels in GCAM are based on rooftop PV supply curves developed for the United States [3].

!   [1] Y. Zhou and S. J. Smith, “Spatial and temporal patterns of global onshore wind speed distribution,” Environmental Research Letters, vol. 8, no. 3, p. 034029, 2013.

!   [2] Y. Zhou, P. Luckow, S. J. Smith, and L. Clarke, “Evaluation of global onshore wind energy potential and generation costs,” Environmental science & technology, vol. 46, no. 14, pp. 7857–7864, 2012.

!   [3] P. Denholm and R. Margolis, “Supply curves for rooftop solar pv-generated electricity for the united states,” 2008.

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Bioenergy Production

Bioenergy Production

Purpose Grown Bioenergy

Crop & Forestry Residues

Municipal Solid Waste

Purpose Grown Bioenergy: •  Production depends on land allocation and regional yield from Ag model •  Land allocation depends on the profit rate of biomass AND all competing land uses •  Includes 1st and 2nd generation crops

Crop & Forestry Residues: •  Potential production depends on crop production in ag model •  Fraction harvested depends on the price of bioenergy; higher prices lead to more production •  Some amount of residue must remain on the field for erosion control

Municipal Solid Waste: •  Potential production depends population and income •  Fraction used for bioenergy depends on the price of bioenergy; higher prices lead to more production

Note: We also model traditional bioenergy. However, it is not added to the bioenergy resource pool and is instead consumed directly by the buildings sector. Similarly, we model 1st generation bioenergy (corn, sugar, oil crops), but it is converted directly to ethanol or diesel and not added to the bioenergy resource pool.

GCAM AG/LU Model

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The Energy System: Structure

Oil Production

Bioenergy Conversion

Electric Power

Generation

Liquids Refining

Hydrogen

N. Gas Production

Coal Production

Bioenergy Production

Gas Processing

Nuclear

Hydro

Solar

Liquids Market

Bioenergy Market

Natural Gas Market

Hydrogen Market

Electricity Market

Wind

Geothermal

Buildings Sector

Industrial Sector

Transport Sector

Coal Market

Uranium

Resource Production Energy Transformation End-Use Final Energy Carriers

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The Energy System: Energy Transformation and Conversion

! Final energy sectors in GCAM consume several fuels: ! Electricity

! Liquid Fuels

! Coal

! Bioenergy

! Gas

! Hydrogen

! Corresponding to each of these is a conversion sector that takes as inputs various resources. ! For example, liquid fuels are produced from bioenergy, conventional and unconventional

oil, coal, and natural gas.

! Conversion sectors can utilize a number of technologies, even for a single input fuel. ! Bioenergy-to-liquids, for example, can be produced through several different

technologies, some with CCS options.

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The Energy System: Bioenergy Pathways

Oil Production

Bioenergy Conversion

Electric Power

Generation

Liquids Refining

Hydrogen

N. Gas Production

Coal Production

Bioenergy Production

Gas Processing

Nuclear

Hydro

Solar

Liquids Market

Bioenergy Market

Natural Gas Market

Hydrogen Market

Electricity Market

Wind

Geothermal

Buildings Sector

Industrial Sector

Transport Sector

Coal Market

Uranium

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The Energy System: Electric Generation

Oil Production

Bioenergy Conversion

Electric Power

Generation

Liquids Refining

Hydrogen

N. Gas Production

Coal Production

Bioenergy Production

Gas Processing

Nuclear

Hydro

Solar

Liquids Market

Bioenergy Market

Natural Gas Market

Hydrogen Market

Electricity Market

Wind

Geothermal

Buildings Sector

Industrial Sector

Transport Sector

Coal Market

Uranium

Resource Production Energy Transformation End-Use Final Energy Carriers

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The Energy System: Electricity Generation

Bioenergy

Electric Power

Generation

Refined Liquids

Coal

Natural Gas

Nuclear

Hydro

Solar

Wind

Geothermal

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The Energy System: Electric Power Plants

! We model several fuels and technologies for generating electric power.

! For example, the current GCAM core has 4 different technology

options for coal power plants: ! Pulverized coal steam plants ! Pulverized coal steam plants with CO2 Capture and Storage (CCS) ! IGCC ! IGCC with CO2 Capture and Storage (CCS)

! Each power plant has a different efficiency, non-energy cost, and emissions factor. ! Which technology is deployed depends on the trade-offs between

emissions and other costs. For example, IGCC with CCS will only deploy with a higher value on CO2 – as in a climate policy scenario.

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The Energy System: Technology Competition

! Economic competition among technologies takes place at many sectors and levels.

! Assumes a distribution of realized costs due to heterogeneous conditions.

! Market share based on probability that a technology has the least cost for an application. ! Avoids a “winner take all”

result. ! “Logit” specification.

45

A Probabilistic Approach

`

Median CostTechnology 1

Median CostTechnology 2

Median CostTechnology 3

Market Price

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The Energy System: Technology Competition

Source: Clarke and Edmonds (1993), McFadden (1974)

∑=

jjj

iii c

cs σ

σ

αα

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

baseyear σ=0 σ=-1 σ=-3 σ=-6 σ=-12 σ=-24 σ=-100

tech2

tech1

Change in technology shares when tech 1’s cost increases by 20%

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The Energy System: Vintaging of Capital

! We assume that capital stock in certain sectors (for example, electric power generation and oil refining sectors) is long-lived.

! This means that a power plant or refinery built in one model period *may* still be in operation many time periods later.

! However, we do not assume that existing capital is always in operation. Once the variable cost exceeds the market price, we begin to shut down existing units. This often occurs when a carbon price is applied.

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Example Results: Electric Generation by Fuel

!   Base Year 2010 calibrated to IEA data. !   Capital Stock vintaging and retirements !   Investments in new capital based on relative costs and

calibrated preferences.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2010 2015 2020 2025 2030 2035 2040 2045 2050

ExaJou

les

Aust&NZElectricGenera5on:Example

nCHP

mSolar

lWind

kHydro

jGeothermal

iNuclear

gBiomass

eOil

cGas

aCoal0

2

4

6

8

10

12

2010 2015 2020 2025 2030 2035 2040 2045 2050

ExaJou

les

SEAsiaElectricGenera5on:Example

nCHP

mSolar

lWind

kHydro

jGeothermal

iNuclear

gBiomass

eOil

cGas

aCoal

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The Energy System: Energy Demand

Industrial Technologies

Transport Technologies

Buildings Technologies

Liquids Market

Bioenergy Market

Natural Gas Market

Hydrogen Market

Electricity Market

Buildings Sector

Industrial Sector

Transport Sector

Coal Market We have detailed representations of

transportation & buildings in all regions.

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The Energy System: Transportation

! Per capita transportation service demands (measured in km/yr) are a function of income and the prices of services.

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

Air

LDV

Rail

Bus

Non-motorized

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

Air

LDV

Rail

Bus

Non-motorized

0

5000

10000

15000

20000

25000

30000

35000

40000

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100

Freight/shippingto

nne-km

/person/yr

Passen

gerk

m/person/yr

Passenger

Freight

Interna8onalShipping

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The Energy System: Transportation

! The choice among modes of transportation in the passenger sector is a function of the cost of travel, the time it takes, and income.

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The Energy System: Transportation

! The choice among fuels within a mode is a function of cost (including capital cost and the cost of fuel)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

2010 2030 2050 2100

USACompactCarSales

Hydrogenfuelcell

Ba;eryelectric

Naturalgas

ICE-Hybrid

ICE

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

Ba.e

ryelectric

Hydrogen

fuelcell

ICE-H

ybrid

ICE

Naturalgas

Ba.e

ryelectric

Hydrogen

fuelcell

ICE-H

ybrid

ICE

Naturalgas

2010 2050

2005$/veh-km

USACompactCarCosts

Fuel

Capitalandnon-fuelO&M

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0

200

400

600

800

1000

1200

1400

2010 2030 2050 2070 2090

Vehiclesperth

ousand

persons

LDVOwnershipratesNorthAmerica

Europe

Russia

Brazil

OthLatAm

Sub-SahAfrica

MidENAfrica

India

OtherS&CentAsia

China

PacificOECD

OtherSEAsia

The Energy System: Transportation

! A wide variety of detailed output variables can be reported for the transportation sector

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

USA Russia Brazil China India

LDVagedistribu/onin2030

<5yr

5-10yr

10-15yr

15-20yr

>20yr

0

10

20

30

40

50

60

70

80

90

100

2010 2030 2050 2070 2090

km/hr

Weightedaveragetransitspeed

USA

Russia

Brazil

China

India

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The Energy System: Energy Demand

Industrial Technologies

Transport Technologies

Buildings Technologies

Liquids Market

Bioenergy Market

Natural Gas Market

Hydrogen Market

Electricity Market

Buildings Sector

Industrial Sector

Transport Sector

Coal Market We have detailed representations of

transportation & buildings in all regions.

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The Energy System: Buildings

Per-capita Residential and Commercial Energy Use in 2010

0" 5" 10" 15" 20" 25"

USA"Canada"Russia"Europe"

Oth"Lat"Am"Brazil"

Sub?Sah"Afr"Mid"E"N"Afr"Other"Asia"Pac"OECD"

India"China"USA"

Canada"Russia"Europe"

Oth"Lat"Am"Brazil"

Sub?Sah"Afr"Mid"E"N"Afr"Other"Asia"Pac"OECD"

India"China"USA"

Canada"Russia"Europe"

Oth"Lat"Am"Brazil"

Sub?Sah"Afr"Mid"E"N"Afr"Other"Asia"Pac"OECD"

India"China"

Other"

Cooling"

HeaI

ng"

GJ#/#person#

Residen.al#

District"Heat"

Biomass"

Coal"

Liquids"

Natural"Gas"

Electricity"

0" 5" 10" 15" 20" 25"

USA"Canada"Russia"Europe"

Oth"Lat"Am"Brazil"

Sub?Sah"Afr"Mid"E"N"Afr"Other"Asia"Pac"OECD"

India"China"USA"

Canada"Russia"Europe"

Oth"Lat"Am"Brazil"

Sub?Sah"Afr"Mid"E"N"Afr"Other"Asia"Pac"OECD"

India"China"USA"

Canada"Russia"Europe"

Oth"Lat"Am"Brazil"

Sub?Sah"Afr"Mid"E"N"Afr"Other"Asia"Pac"OECD"

India"China"

Other"

Cooling"

HeaI

ng"

GJ#/#person#

Commercial#

District"Heat"

Biomass"

Coal"

Liquids"

Natural"Gas"

Electricity"

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The Energy System: Buildings

! Future evolution of building energy use is shaped by... ! Residential and commercial floorspace

! Population, GDP, and exogenous per-capita floorspace satiation levels

0"

50"

100"

150"

200"

250"

300"

350"

400"

450"

2005"2015"2025"2035"2045"2055"2065"2075"2085"2095"

Billion

&m2&

Total&Building&Floorspace&

USA"

Canada"

Russia"

Europe"

Other"La@n"America"

Brazil"

SubGSaharan"Africa"

Middle"East"&"N."Afr."

Other"Asia"

Pacific"OECD"

India"

China"

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The Energy System: Buildings

! Future evolution of building energy use is shaped by... ! Residential and commercial floorspace ! Levels of building service demands per unit floorspace

! Climate, building shell conductivity, GDP, and exogenous satiation levels

0"

0.02"

0.04"

0.06"

0.08"

0.1"

0.12"

2010"

2020"

2030"

2040"

2050"

2060"

2070"

2080"

2090"

2100"

MJ#/#DD#/#m

2#

Residen.al#Cooling#

USA"

Canada"

Russia"

Europe"

Oth."Lat."Amer."

Brazil"

SubFSah."Afr."

Mid."E."&"N."Afr."

Other"Asia"

Pacific"OECD"

India"

China"0"

0.05"

0.1"

0.15"

0.2"

0.25"

2010"

2020"

2030"

2040"

2050"

2060"

2070"

2080"

2090"

2100"

MJ#/#DD#/#m

2#

Residen.al#Hea.ng#

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The Energy System: Buildings

! Future evolution of building energy use is shaped by... ! Residential and commercial floorspace ! Levels of building service demands per unit floorspace ! Fuel and technology choices by consumers

0"

5"

10"

15"

20"

25"

30"

35"

40"

45"

2010"2050"2100" 2010"2050"2100" 2010"2050"2100" 2010"2050"2100" 2010"2050"2100" 2010"2050"2100"

Brazil" China" India" Russia" USA" EU:27"

EJ/yr&

Othr:"Electricity"

Othr:"Heat"

Othr:"Liquids"

Othr:"Gas"

Othr:"Coal"

Othr:"Biomass"

Clng:"Electricity"

Htng:"Electricity"

Htng:"Heat"

Htng:"Liquids"

Htng:"Gas"

Htng:"Coal"

Htng:"Biomass"

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The Energy System: Calibration

! The current base year for the energy system is 2010.

! We use IEA energy balances as calibration data.

! The calibration procedure calculates “share weights” such that the dataset derived from the IEA energy balances is reproduced.

! These share weights reflect unmeasured and non-economic influences on decision-making.

! If a technology has low costs but nevertheless has low market share (e.g. coal furnaces), then the model will compute a low share weight. If this base-year share weight is applied to future periods, then the market share of the technology will remain low even if it remains a relatively low-cost option.

! In most cases, we retain these share weights in future years. In some cases (e.g. renewables in the electric sector, or alternative-fuel vehicles in the LDV sector), we have over-written them because the base-year shares do not reflect mature market equilibrium conditions.

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The Energy System: Results

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The Energy System: Results

Primary Energy Inputs to Industrial Electricity

0

0.5

1

1.5

2

2.5

3

0

20

40

60

80

100

120

140

160

180

2001990

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100

Prim

ary/Fina

lCoe

fficien

t

EJ/yr

geothermal

solar

wind

hydro

biomass

nuclear

oil

gas

coal

intensity

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Frequently Asked Questions

! Common question: ! Why are some of the energy

prices in GCAM lower than recent history or other projections?

! Answer: ! We are a long-term equilibrium

model. We do not attempt to capture short-term market fluctuations or market behavior.

! In the case of oil, we do not sustain higher oil prices because the cost of substitutes (e.g., CTL, GTL) is lower than the current market price.

Oil Price

0

20

40

60

80

100

120

1965 1975 1985 1995 2005 2015

$/ba

rrel

EIA Nominal EIA Real (2010$) GCAM Real (2010$)

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AGRICULTURE AND LAND USE

63

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The Global Change Assessment Model

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The Agricultural System: Demand

! GCAM currently models supply and demand for 12 crops, 6 animal categories, and bioenergy: ! Crops: corn, rice, wheat, sugar, oil crops (e.g., soybeans), other grains

(e.g., barley), fiber (e.g., cotton), fodder (e.g., hay, alfalfa), roots & tubers, fruits & vegetables

! Animals: beef, dairy, pork, poultry, sheep/goat, other ! Forest: roundwood ! Bioenergy: switchgrass, miscanthus, jatropha, willow, eucalyptus, corn

ethanol, sugar ethanol, biodiesel (from soybeans and other oil crops)

! We account for both food and non-food demand, including animal feed.

! Demand is modeled at the 32 region level.

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The Agricultural System: Demand

! Non-food, non-feed demand: ! Base year demand for non-food, non-feed uses FAO statistics ! Future demand:

! Per capita demand for crops, animals, and forestry products is currently fixed. ! Thus, demand grows proportional to population, regardless of income or price.

! Feed demand: ! Base year demand for feed combines FAO statistics with data from the

IMAGE model (PBL) ! Future demand:

! Depends on the growth in animal consumption, as well as the change in relative prices of feed options

! Animal can either be grass-fed or grain-fed. The exact proportion of grass- vs. grain-fed depends on the price of pasture land as compared to the price of crops

! Grain-fed animals can shift their diet as the relative prices of various crops change. However, the elasticity is relatively low to prevent dramatic shifts that may comprise an unsustainable diet.

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The Agricultural System: Demand

! Food demand: ! Base year demand for food uses FAO statistics ! Future demand in the baseline is calibrated to match FAO projections of

crop and meat demand through 2050. After 2050, we assume that per capita demand is constant.

! Meat demand in GCAM is price responsive. As the price of meat increases, meat demand will decline.

! The current price elasticity is very low (~0.25). This is consistent with USDA data for the USA and Australia. Developing countries typically have more elastic demand, but our default assumption is very conservative.

! Crop demand is not price responsive.

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The Global Change Assessment Model

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The Agricultural System: Technologies

! For each crop and region, we have started with a single production technology. ! The yield for this technology is calculated from GTAP/FAO statistics, by

dividing total production in a region by land area. ! GCAM results are production per year, not per harvest. Thus, we use

total physical crop land area to calculate yield and not harvested area. If a region actually harvests more than once a year, their “economic” yield (used by GCAM) will be larger than the actual physical yield.

! We exogenously specify technical change for agricultural technologies. ! We use FAO projections through 2050. ! After 2050, we assume that yields will improve by 0.25% per year for all

crops and regions.

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The Global Change Assessment Model

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! The world is divided into 283 regions

The Agricultural System: Basic Assumptions

71

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The Agricultural System: Regions

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The Agricultural System: Regions

Monfreda et al. (2009)

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283 Different AgLU Supply Regions

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! The world is divided into 283 regions ! Farmers allocate land across a variety of uses in order to maximize

profit ! There is a distribution of profits for each land type across each of the

283 regions ! The actual share of land allocated to a particular use is the probability

in which that land type has the highest profit ! The variation in profit rates is due to variation in the cost of production

! As the area devoted to a particular land use expands, cost increases ! Yield is fixed within each region for each crop management practice

The Agricultural System: Basic Assumptions

75

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The Agricultural System: Nesting

Corn, wheat, etc.

Corn, wheat, etc.

Corn, wheat, etc.

Corn, wheat, bioenergy, etc.

Land

Non-Pasture

Grass and Shrubs

Pasture

Other Pasture

Intensively-Grazed PastureCrops All

Forests

ForestCommercial Forest

Tundra Rock, Ice,Desert UrbanArable Land

Shrubland

Grassland

Other arable land

Gray = ExogenousGreen = Non-commercialRed = Commercial

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The Agricultural System: USA Wheat Yield

While yield is fixed within each subregion, there is a

distribution of yields across each of the 32 GCAM regions.

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The Agricultural System: Calibration

! Currently, we calibrate to an average of 2008-2010 data. This is to avoid using an anomalous weather year as a benchmark.

! During the AgLU calibration process, the model computes the average profit rate required to reproduce the base year land allocations. We assume that the difference between this profit and the observed profit (yield * (p – c)) is a cost to production that also applies in the future.

! Thus, if you have a region with a high crop yield, but low land allocation in the base year (e.g., Wheat in Alaska), the model assumes that there are some additional costs that must be considered when expanding its land area. As a result, that crop will continue to have a low share in the future in the absence of a technology or policy change.

Wheat production in USA AEZ16

0.00000%

0.00002%

0.00004%

0.00006%

0.00008%

0.00010%

0.00012%

2000 2050 2100

% o

f glo

bal p

rodu

ctio

n

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0%#10%#20%#30%#40%#50%#60%#70%#80%#90%#100%#

Base%Year%

σ%=%0%

σ%=%0.1%

σ%=%0.5%

σ%=%1%

σ%=%2%

σ%=%3%

σ%=%4%

σ%=%5%

σ%=%6%

σ%=%7%

σ%=%8%

σ%=%9%

σ%=%10%

σ%=%50%

σ%=%100%

Land#Type#1# Land#Type#2#

The Agricultural System: Land Competition

Source: Clarke and Edmonds (1993), McFadden (1974)

si =αiπ i( )σ

α jπ j( )σ

j∑

Change in land shares when land type 1’s profit increases by 20%

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The Agricultural System: Land Competition

! Elasticities can be computed at each point, but ! By design, there is not a constant elasticity relationship with respect to

changes in profit

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The Agricultural System: Land Cover Data

Potential Vegetation

Cropland area

Crop-specific harvested areas

Maize Area in 2010

Sub-national Harvested areas

!   GCAM needs land cover by type (e.g., forest, grass, maize, wheat, etc.) for each region/AEZ combination in each historical year.

!   We have similar methodologies in other sectors: !  Population: IIASA, US Census !  Energy: IEA, EIA, country

studies !  Agriculture: FAO, GTAP, MIRCA !  Emissions: EDGAR, EPA, RCP

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The Global Change Assessment Model

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The Agricultural System: Supply

! Yield is exogenously calculated. ! Base year derived from GTAP/FAO production and land area. ! Yields increase over time based on exogenously specified technical

change.

! Land area is endogenously calculated. ! Each land types share of area in its region is the probability its profit is the

highest in that region.

! Supply = land * yield

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The Agricultural System: Results

Global Beef Feed Beef Consumption by Region

0

20

40

60

80

100

120

140

160

1990

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100

PCal

USA Southeast Asia South Korea South Asia South America_Southern South America_Northern South Africa Russia Pakistan Middle East Mexico Japan Indonesia India European Free Trade Association Europe_Non_EU Europe_Eastern EU-15 EU-12 Colombia China Central Asia Central America and Caribbean Canada Brazil Australia_NZ Argentina Africa_Western Africa_Southern Africa_Northern Africa_Eastern

0

1000

2000

3000

4000

5000

6000

1990

2005

2010

2015

2020

2025

2030

2035

2040

2045

2050

2055

2060

2065

2070

2075

2080

2085

2090

2095

2100

Mt

Scavenging_Other Pasture_FodderGrass

FodderHerb_Residue FeedCrops

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The Agricultural System: Results

Wheat Production by Region Wheat Production in the USA

0

100

200

300

400

500

600

700

800

900

1000

1990

2010

2020

2030

2040

2050

2060

2070

2080

2090

2100

Mt/y

r

USA

Southeast Asia

South Korea

South Asia

South America_Southern

South Africa

Russia

Pakistan

Middle East

Mexico

Japan

India

European Free Trade Association

Europe_Non_EU

Europe_Eastern

EU-15

EU-12

Colombia

China

Central Asia

Central America and Caribbean

Canada

Brazil

Australia_NZ

Argentina

Africa_Western

Africa_Southern

Africa_Northern

Africa_Eastern 0

20

40

60

80

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2005

2010

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2085

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2095

2100

Mt/y

r

WheatAEZ16 WheatAEZ15 WheatAEZ14 WheatAEZ13 WheatAEZ12 WheatAEZ11 WheatAEZ10 WheatAEZ09 WheatAEZ08 WheatAEZ07

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The Agricultural System: Results

0

100

200

300

400

500

600

700

800

900

1000

1990 2015 2030 2045 2060 2075 2090

Mt/y

r NonFoodDemand_Crops

FoodDemand_Crops

FeedCrops

Wheat Consumption by Use

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The Agricultural System: Results

Global Land Allocation

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The Global Change Assessment Model

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! While we can explain the energy and agricultural systems separately, these two systems cannot be separated in practice. Choices made in one sector affect outcomes in another sector.

! This is true both in the real world and in GCAM. You cannot run the different components of the model separately.

! GCAM currently has three means of linking the energy and agriculture systems: ! Bioenergy: supplied by the agricultural system, demanded by the energy

system ! Fertilizer: supplied by the energy system, demanded by the agricultural

system ! DDGS: supplied by the energy system, demanded by the agricultural

system

The Agricultural System: Linking the Energy & Agricultural Sectors

89

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Fertilizer Supply

! We are modeling synthetic fertilizer production for use in the agricultural sector. We do not include non-agricultural uses of fertilizer or natural fertilizer.

! Production by technology is from IEA.

Global fertilizer production by fuel

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05

2010

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20

55

2060

20

65

2070

20

75

2080

20

85

2090

20

95

2100

MtN

refined liquids

gas

coal

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Fertilizer Demand

! Consumption by country (and therefore region) are from FAO ResourceSTAT.

! Consumption by region is first downscaled to crops according to a dataset put together by the International Fertilizer Industry Association working in collaboration with the FAO, and then downscaled to AEZ on the basis of crop production.

Global fertilizer consumption by crop

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MtN

biomass

Wheat

SugarCrop

Root_Tuber

Rice

PalmFruit

OtherGrain

OilCrop

MiscCrop

FodderHerb

FodderGrass

FiberCrop

Corn

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Joint GCAM Community Modeling Meeting and GTSP Technical Workshop Joint Global Change Research Institute College Park, Maryland, USA

Introduction to the Global Change Assessment Model (GCAM) THE JGCRI GCAM TEAM

Thursday, December 3, 2015

PNNL-SA-90713

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Outline

! Brief introduction to Integrated Assessment Models

! Overview of GCAM

! Detailed information on GCAM’s ! Economic assumptions, ! Energy system, ! Agriculture and land use system, ! Emissions, ! Policies, ! Climate system, and ! Solution algorithm.

! Frequently asked questions

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POLICY MARKETS

94

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The Global Change Assessment Model

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Other Markets: Climate Policy

! Carbon or GHG prices: ! Users can specify the price of carbon or GHGs directly ! Emissions will vary depending on other scenario drivers

! Emissions constraints: ! Users can specify the total amount of emissions (CO2 or GHG) ! Model will calculate the price of carbon needed to reach the constraint

! Climate constraints: ! Users can specify a climate variable (e.g., concentration or radiative forcing) target

for a particular year ! Users determine whether that target can be exceeded prior to the target year ! Model will adjust carbon prices in order to find the least cost path to reaching the

target ! (This type of policy increases model run time significantly)

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Other Markets: Energy Policy

! We can impose constraints (lower & upper bounds) on energy consumption. ! The model will solve for the tax (upper bound) or subsidy (lower bound)

required to reach the given constraint. ! Within an individual sector, these constraints can be share constraints

(e.g., fraction of electricity that comes from solar power). ! This allows us to model renewable portfolio standards and biofuels standards.

! Across sectors, these must be quantity constraints.

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Other Markets: Land-Use Policy

! REDD: ! In this policy, we set aside some land from economic competition. This land

cannot be converted to crops, pasture, or any other land type. ! Currently, this is the core assumption in GCAM when running a carbon policy.

! We have protected 90% of non-commercial ecosystems.

! Valuing carbon in land: ! In this policy, we assume that land use change emissions are taxed at the

same rate as fossil fuel and industrial emissions. ! Land owners receive a subsidy proportional to their carbon content.

! Bioenergy constraints (upper or lower): ! We can also constrain biomass to a particular level. This is implemented in

GCAM as a tax or subsidy on bioenergy consumption. The tax/subsidy is adjusted until the constraint is met.

! Bioenergy taxes: ! We can impose a tax on bioenergy that is linked to the carbon price.

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! Imposing a climate policy affects the cost of energy production for carbon-intensive fuels. This induces a shift toward lower emitting technologies.

Other Markets: The Effect of Climate Policy on the Energy System

Cost of Electricity Generation in China

Electricity Generation in China in 2050

0

5

10

15

20

25

30

35

40

Reference Tax ($25/tC in 2020)

EJ/y

r

m Solar

l Wind

k Hydro

j Geothermal

i Nuclear

h Biomass w/CCS

g Biomass

f Oil w/CCS

e Oil

d Gas w/CCS

c Gas

b Coal w/CCS

a Coal

0

2

4

6

8

10

12

14

16

18

20

coal (IGCC) coal (IGCC CCS) Gen_III

1975

$/G

J

Reference

Policy

99

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! Under the default assumption in GCAM, 90% of non-commercial ecosystems are protected in GCAM. This means that they cannot be used for crop or bioenergy production.

Other Markets: The Effect of Climate Policy on the Agriculture & Land-Use System

100

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0

20

40

60

80

100

120

140

0.0 1.0 2.0 3.0

$ / t C

A b a te m e n t (G tC / y r )

0

1

2

3

4

5

6

7

8

9

10

0 20 40 60 80 100

Pric

e

Quantity

Other Markets: Climate Policy Cost

! GCAM can compute the cost of a climate policy endogenously. ! The cost metric used is the area under the marginal abatement cost (MAC)

curve. This area under the MAC curve commonly referred to as “deadweight loss” (i.e., the change in producer and consumer surplus.)

! Currently, we are not modeling this cost as affecting GDP in GCAM.

Marginal Abatement Cost “Deadweight loss”

Tax Revenue

Supply

Demand

Original Quantity

New Quantity

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Frequently Asked Questions

! Common question: ! Does the GCAM reference scenario include other climate and energy

policies?

! Answer: ! To the extent that these exist in the base year, they will be calibrated into

the GCAM reference scenario. ! However, we do not explicitly include any proposed climate or energy

policies in the reference scenario.

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TRADE

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The Global Change Assessment Model

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Current Approach to Modeling Trade

! In general, we model Heckscher-Ohlin trade. We have not focused on bilateral trade.

! This means that for many products, we assume that trade occurs freely into and out of global markets. These products include coal, gas, oil, bioenergy, food, and fiber. ! A region’s net trade position is dynamic depending on economics,

technical change, demand growth, resources, and other changing factors. ! In simplest terms – given a global market price – each region computes

demand and production, and net imports are the difference.

! For other products, we have fixed or static interregional trade. These products include solar, wind, geothermal, meat, and dairy. ! For some products, like solar resources, trade is physically impractical if

not infeasible. ! For other products such as beef, our basic economic modeling approach

makes dynamic trade complicated, and the fixed trade assumption based on historical data is a conservative approach.

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! Collection and Processing ! Pelletizing important to

increase the energy density of the fuel and facilitate transportation

! Average cost to transport to local collection facility and pelletize of $2.18/GJ (2005$) ! 85% of cost is in pelletizing ! compare to $1.33/GJ for

Coal (Edwards). ! International transport cost of

$0.31/GJ (2005$) added to all regions (assumes large ocean bulk carriers)

Interregional Trade: the case of Bioenergy

(Van Vliet, 2009, consistent with Wolf 2006)

We model large scale bioenergy systems

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Future Goals and New Approaches in Development for Modeling Trade

! We have several recent efforts where we have either goals or plans to go beyond the simple global market approach. ! Dynamically combine regionally differentiated product markets with global

or multiregional markets. ! Allow ability to model effect of regional isolation or difficulty in participating

in inter-regional markets (e.g., short-term constraints to imports). ! Unlike some Armington implementations, allow long-term dynamic

change of regional product import/export positions in response to economics.

! We have initial implementations differentiating demand from domestic and global (or extra-regional) markets. ! Combines intra-regional production as currently modeled with statistical

(logit) parametric sharing of interregional trade in global market. ! Still requires more development and vetting, possibly simplifying. ! Natural gas production and markets to address need for LNG for global. ! Would allow dynamic trade in current fixed trade products like beef. ! Project task for DOE to model trade limits/implications of climate impacts

on food demand in vulnerable regions.

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EMISSIONS

108

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Emissions: Modeling in GCAM

109

Emissions = Em_ factor•Activity_ Level • 1−Em_Controls(GDPper−capita )( )

In an IAM we need to represent future emission trajectories and how those trajectories might vary under different drivers and policies.

CO2: GCAM is a process model for CO2 emissions and reductions ! Emissions depend on specific technologies, whose use is explicitly determined by the

model, and can be modified through carbon prices. ! The GCAM, in effect, produces a Marginal Abatement Curve for CO2

Non-CO2 GHGs: are modeled as

Air pollutant emissions: (SO2, NOx, etc.) are modeled as:

Non-CO2 emissions (both GHGs & air pollutants) originate from many sources and can be controlled using multiple abatement technologies

! This is too much detail for us to include explicitly at the process level ! We calibrate to base year inventories and use parameterized functions for future emissions

controls and Marginal Abatement Cost (MAC) curves to change emission factors over time. ! Technology shifts still play a role, since emission factors differ between technologies.

Emissions = Em_ factor•Activity_ Level • 1−MAC(Carbon - Price)( )

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Emissions: Base Year Emissions

GCAM tracks emissions for a number of greenhouse gases and air pollutants ! CO2, CH4, N2O, CF4, C2F6, SF6, HFC23, HFC32, HFC43-10mee, HFC125, HFC134a,

HFC143a, HFC152a, HFC227ea, HFC236fa, HFC245fa, HFC365mfc, SO2, BC, OC, CO, VOCs, NOx, NH3

! We calculate CO2 from fossil fuel & industrial uses, as well as from land-use change

! CO2: ! Energy system: we read in global carbon contents for fossil fuels (e.g., coal, gas,

oil). These are chosen so we match global emissions from CDIAC in the base year. These carbon contents are used to compute emissions in all years (including the base year).

! LUC: we read in carbon density, growth parameters, and historical land allocation and compute emissions in all years (including the base year).

! Non-CO2: ! 2005 emissions calibrated to match the EDGAR* data set (except BC & OC, where

we use RCP inventories). In some cases (e.g., electricity), we supplement EDGAR with EPA to get technology-specific emissions.

! We plan to update GCAM calibration to the newly released CEDS historical emissions dataset, which currently extends to 2014. globalchange.umd.edu/ceds

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Emissions: Vegetation CO2 Emissions

! First, we determine the total change in carbon stock for each land type and region. ! Δ C Stock = [Land Area (t)]*[C density (t)] - [Land Area (t-1)]*[C density

(t-1)]

! Then, we allocate that change across time. ! If change in land area decreases the carbon stock (e.g., deforestation),

then all carbon is released into the atmosphere instantaneously. ! If the change in land area increases the carbon stock (e.g., afforestation),

then carbon accumulates slowly over time, depending on an exogenously specified mature age.

! The mature age varies by land type and region.

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Emissions: Forest Carbon Uptake

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 20 40 60 80 100

35 years

50 years

75 years

100 years

Years since land conversion

% o

f eve

ntua

l car

bon

stoc

k

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Emissions: Soil CO2 Emissions

! First, we determine the total change in carbon stock for each land type and region. ! Δ C Stock = [Land Area (t)]*[C density (t)] - [Land Area (t-1)]*[C density (t-1)]

! Then, we allocate that change across time. ! Whether carbon stock increases or decreases, we use the same formula.

! ! The half life, λ, varies by region. ! In general, colder regions have longer soil carbon half lives.

!"#$%&'(") ! = !!"#$%&'(") 0 + !∆!"#$%&'(")!"#$%!,! ∙ (1− !!!")!

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Emissions: Non-CO2 Drivers

Energy System ! Emissions in the energy system can be driven by input (e.g., fuel

consumed by a particular technology) or output (e.g., fuel or service produced by a particular technology).

! Emissions information is technology-specific. As a result, different technologies that produce the same output can have different emissions per unit of activity.

! For most gases and species, we model drivers of emissions in detail. However, for some F-gases, the driver data (e.g., fire extinguishers) depends only on GDP.

Agriculture ! Emissions in the agricultural system can be driven by output (e.g., for

crop production) or land area (e.g., for open burning). ! Emissions information is crop and region specific in GCAM. However,

inventory data is region specific, but not crop specific (or AEZ specific).

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GCAM Non-CO2 Emissions: Projections

115

Air Pollutant Emissions ! Projections currently use a global parameterization where emission

factors decline as a function of GDP per capita ! This species-specific parameterization captures the general trend of increasing pollutant

controls over time. ! This does not capture regional and technological heterogeneity. Future updates to this

are planned. ! Note that the GCAM implementation of the SSP scenarios used a different approach,

incorporating region, sector, and fuel specific pollutant emission factor pathways (Calvin et al 2016, Rao et al. 2016).

Non-CO2 GHG Emissions ! GHG emission factors only change due to MAC curves

! Where a MAC curve is present, the emissions factor changes in two ways •  Below-zero (e.g. “no cost”) MAC mitigation (e.g. MAC reduction percentage is > 0 at

zero carbon price) are applied in the reference case. (can be turned off by setting no-zero-cost-reductions to 1 within a MAC curve).

•  Under a carbon policy, the emission factor is reduced, as a function of the carbon price, as specified by the MAC curve.

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Emissions: Fluorinated Gases

! Fluorinated gas emissions are linked either to the size of the industrial sector (e.g., semiconductors) or to GDP (e.g., fire extinguishers). As those drivers change, emissions will change. Additionally, we include abatement options based on the EPA’s most recent MAC curves.

! For HFC134a from cooling (e.g., air conditioners), we make additional adjustments to emissions factors in the developing regions to reflect their continued transition from CFCs to HFCs (see EPA report).

HFC134a Emissions

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2500

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2010

2020

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Gg

HFC

134a

USA Taiwan Southeast Asia South Korea South Asia South America_Southern South America_Northern South Africa Russia Pakistan Middle East Mexico Japan Indonesia India European Free Trade Association Europe_Non_EU Europe_Eastern EU-15 EU-12 Colombia China Central Asia Central America and Caribbean Canada Brazil Australia_NZ Argentina Africa_Western Africa_Southern Africa_Northern Africa_Eastern

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Emissions: Results

USA Methane Emissions USA Sulfur Emissions

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80

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20

10 20

20 20

30 20

40 20

50 20

60 20

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80 20

90 21

00

TgC

H4/

yr

Urban Processes

Industrial Processes

Industry

Transportation

Residential

Commercial

Refining

Hydrogen

Electricity

Energy Production

Forest/Savannah Burning

Other Crops

Rice

Livestock

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30 20

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60 20

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00

TgSO

2/yr

Urban Processes

Industrial Processes

Industry

Transportation

Residential

Commercial

Refining

Hydrogen

Electricity

Energy Production

Forest/Savannah Burning

Other Crops

Rice

Livestock

Emissions are produced at a region level (32 regions for energy, 283 regions for agriculture & land-use).

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GCAM Non-CO2 Emissions: User Options

118

GHG Emissions ! Emissions prices of different GHGs can be linked together for a multi-gas

policy using the linked-ghg-policy object (for example, linked_ghg_policy.xml). The parameter price-adjust is used to convert prices (e.g., 100 year GWP) and demand-adjust is used to convert demand units (e.g., to common units of carbon equivalents). ! These can be changed by year if desired. ! Setting price-adjust to zero means that there is no economic feedback for the

price of this GHG. MAC curves, however, will still operate. This can be changed separately for energy/industrial/urban CH4, agricultural CH4 (CH4_AGR), and CH4 from agricultural waste burning (CH4_AWB), LUC CO2 emissions (e.g. CO2_LUC).

This flexibility allows CO2-only or CO2-equivalant markets/constraints for various “baskets” of emissions as needed.

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New GCAM Non-CO2 User Options

119

These will be part of the next incremental release. ! MAC curves can be set for any emission species. (e.g., CH4-only market,

NOx market, etc.)

! Below zero MAC reductions phased in over several years (default 25 years, with optional user-defined time period).

! GHG objects can be added/changed via user input in any time period (currently GHG objects must first appear in 1975 and cannot be changed).

! MAC curves can be set to operate only before a specific vintage year (useful for combining pollutant emission MAC curves with new source standards).

! New linear-control object allows user to specify that an emission factor will go to a user-defined value over a specified time period.

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CLIMATE

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The Global Change Assessment Model

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The Climate System: Approach

* GCAM includes more HFCs than are included in MAGICC. We map missing gases to those with similar lifetimes based on GWP. Meinshausen et al., 2011

! GCAM default climate module is now Hector with the option to run MAGICC5.3 ! Inputs:

! GCAM passes emissions to the climate model ! Fossil fuel & Industrial CO2, Land-Use Change CO2, CH4, N2O, SF6, C2F6, CF4,

HFC125, HFC134a, HFC143a, HFC227ea, HFC245fa*, SO2, CO, NOx, NMVOCs, BC, OC

! Outputs: ! MAGICC and Hector compute concentrations and radiative forcing ! Computes atmospheric CO2, temperature change, air-land/air-sea fluxes, SLR

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Why develop a new simple climate model?

!   MAGICC !   Used across many scientific and policy communities –

instrumental in the IPCC !  Many strengths !  Old code to work with !   Not open source, legal issues unclear

!   Developed Hector !   Free and open-source – community model

! www.Github.com/JGCRI/hector !   Easy to use and well documented

!  Hartin et al., 2015 - GMD !  Hartin et al., 2016 - BGS

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Hector philosophy and structure

!   Complexity only where warranted !   Modular

!   Components can be enabled/disabled via inputs !  E.g. you can test two different ocean submodels against each

other

!   Modern, clean structure !   E.g. coupler enforces unit checking between submodels

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Hector: open and object –oriented architecture

!   Initialization !   Input data are routed to

model components via the model core

!   Spin up !   the carbon cycle is in

equilibrium before the main run starts

!   Main run

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Hector: open and object –oriented architecture

126

! Components have a defined interface (API)

! They register their dependencies and capabilities with the core ! e.g., sea level rise depends on

temperature ! Core orders components by their

dependencies ! Components query the core for

data ! Core routes request to

appropriate component SLR Core

My name is SLR and I provide sea

level rise data

Got it

I depend on mean global temperature

Okay

Hello

During initialization

SLRCoreX

I need current sea level rise

Hold onSomeone needs

sea level riseI warned you I'd

need temperature for this

Temperature

Yes, it's already been calculated…here

Temperature please

Here you go

Here's sea level rise

Here you are

As the model runs

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; Config file for hector model: RCP4.5 [core] run_name=rcp45 startDate=1745 endDate=2100 do_spinup=1 ; if 1, spin up model before running (default=1) max_spinup=5000 ; maximum steps allowed for spinup (default=2000) [onelineocean] enabled=0 ; putting 'enabled=0' will disable any component ocean_c=38000, Pg C [ocean] enabled=1 ; putting 'enabled=0' will disable any component

spinup_chem=0 ; run surface chemistry during spinup phase? tt = 72000000 ; 7.2e7 thermohaline circulation, m3/s tu = 49000000 ; 4.9e7 high latitude overturning, m3/s twi = 12500000 ; 1.25e7 warm-intermediate exchange, m3/s tid = 200000000 ; 2.0e8 intermediate-deep exchange, m3/s k = 0.2 ; ocean heat uptake efficiency (W/m2/K) [simpleNbox] ; Initial (preindustrial) carbon pools atmos_c=588.071 ; Pg C in CO2, from Murakami (2010) veg_c=550 ; Pg C detritus_c=55 ; Pg C soil_c=1782 ; Pg C

Sample Input File

Initial values for the ocean and land

components

127

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Hector: Science

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Hector: Atmosphere

!   Well mixed globally averaged atmosphere !   Forced with emissions from RCP scenarios

!   CO2 – anthropogenic & LUC

!   BC/OC !   CH4/N2O !   26 halocarbons ! Sulphate aerosols !   Volcanic emissions

!   Calculate: !   Stratospheric H2O !   Tropospheric O3

!   Radiative forcing !   include both indirect and direct effects on radiative forcing

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Science: Land

130

! A classic simple design: five boxes

! NPP, RH, litter fluxes scaled by global temperature and CO2

! Optional biomes – ex. Boreal and tropical

! Continual mass balance to check for ‘leaks’

Atmosphere

Earth

Vegetation

Detritus

Soil

LAND

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Science: Ocean

131

! 4 boxes ! 2 surface boxes (100m) ! Intermediate box ! Deep box (~3777m)

! Advection and water mass exchange

! Heat uptake in surface boxes ! Carbon chemistry in surface

boxes (e.g., atmosphere-ocean flux, pH, CaCO3 saturations)

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The Climate System: Results

Hartin et al., 2015 - GMD

1950 2000 2050 2100 1900 1850

Atmospheric CO2 – RCP8.5

Radiative Forcing

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The Climate System: Results

1900 1950 2000 2050 2100 -2

0

1850

2

4

6

1900 1850 1950 2000 2050 2100 1900 1850

Atmospheric Temperature – RCP8.5

Ocean pH – RCP8.5

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Energy

Water

Land

Socioeconomics

Climate – Hector + capabilities

GCAM integration of Hector

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QUESTIONS?