IPCC SR1.5
Chapter 4:
Strengthening andimplementing the
global response
COP 24, IPCC Pavilion
December 6, 2018

Chapter 4’s authors
CLAs: Heleen de Coninck (Netherlands/EU), Aromar Revi
(India)LAs: Mustafa Babiker (Sudan), Paolo Bertoldi (Italy), Marcos
Buckeridge (Brazil), Anton Cartwright (South Africa), Wenjie
Dong (China), James Ford (Canada/UK), Sabine Fuss
(Germany), Jean-Charles Hourcade (France), Debora Ley(Guatemala/Mexico), Reinhard Mechler (Germany), Peter
Newman (Australia), Anastasia Revokatova (RussianFederation), Seth Schultz (USA), Linda Steg (Netherlands),
Taishi Sugiyama (Japan)
CSs: Kiane de Kleijne (Netherlands/EU), Chandni Singh(India)Ashley Cooper / Aurora Photos

Report’s key messages
Already 1°C of global warming, at current rate, would
reach 1.5°C around 2040
Clear benefits to limiting warming to 1.5°C
We can still limit warming to 1.5°C
Unprecedented changes needed

Current action is insufficient
Limiting warming to 1.5°C would go hand in handwith achieving other societal goals
Ashley Cooper / Aurora Photos

Outline of the presentations
Starting points and approach of chapter 4
System transitions, options and CDR
Feasibility of selected mitigation and adaptation
options
Enabling conditions for system transitions
Two deep dives:• Adaptation: incremental or transformational?
• The finance and economics of the SR1.5

Ashley Cooper / Aurora Photos

Structure of chapter 4
4.1 Accelerating the global response to climate change
4.2 Pathways compatible with 1.5C: starting points
4.3 Systemic changes for 1.5C-consistent pathways
4.4 Implementing far-reaching and rapid change
4.5 Integration and enabling transformation
4.6 Knowledge gaps and key uncertainties

Structure of chapter 4
Enabling conditions:

System transitions:
Energy, land & ecosystems, urban& infrastructure, industry

PolicyFinanceInnovation

Mitigation and adaptation
options, and their feasibility

Behaviour change
Institutional capacity
Multi-level governanceFeasibility of options in system transitions
Mitigation and adaptation
options assessed along six
dimensions
Result: where should apolicymaker look first for
quick wins? Where are gaps
in knowledge? And whatbarriers need to be
overcome?

Feasibility Framework•Systematize the assessment of adaptation and mitigation options at the
global level•Feasibility: The degree to which climate goals and response options are
considered possible and/or desirable (SR1.5 Glossary)•Assess along six dimensions of feasibility• Economic: Are necessary economic and financial conditions present?
• Technological: Are the options mature/is there technical/technological capacity?
• Institutional: Do institutional and political conditions support the option?
• Socio-cultural: Is the option socially and culturally acceptable, and inclusive?
• Environmental/ecological: Does the option increase ecosystem services or enhance
resilience / adaptive capacity?
• Geophysical: Does the capacity of physical systems to support the option?

•Context-dependent: reflected per option•Grounded in peer-reviewed literatureIndicators for mitigation and adaptation differ slightly
Dimensions

Economic

Adaptation indicators
Micro-economic viability
Macro-economic viability
Socio-economic vulnerability reduction potential
Employment & productivity enhancement
potential

Mitigation indicators
Cost-effectiveness
Absence of distributional effects
Employment & productivity enhancement
potential

TechnologicalTechnical resource availability
Risks mitigation potential

Technical scalability
Maturity
Simplicity
Absence of risk

Institutional

Political acceptability
Legal & regulatory feasibility
Institutional capacity & administrative feasibility
Transparency & accountability potential

Political acceptability
Legal & administrative feasibility
Institutional capacity
Transparency & accountability potential

Socio-cultural

Social co-benefits (health, education)
Socio-cultural acceptability
Social & regional inclusivenessIntergenerational equity

Social co-benefits (health, education)
Public acceptanceSocial & regional inclusivenessIntergenerational equity
Human capabilities

Environmental Ecological capacity/ ecological
Adaptive capacity/ resilience building potential

Geophysical

Reduction of air pollution
Reduction of toxic waste
Reduction of water use
Improved biodiversity

Physical feasibility
Land use change enhancement potential
Hazard risk reduction potential

Physical feasibility (physical potentials)
Limited use of land
Limited use of scarce (geo)physical resources
Global spread

Total:19 indicators

Total: 24 indicators

Assessment Process• Two rounds of internal review to select literature• Each option’s indicator-level assessment was validated by atleast three experts• If indicator-level assessment differed, it was discussed andreconciled• This discussion also informed the “Context” column of Table
4.11 and 4.12
• Line of sight to specific articles relevant to each indicator (seeSupplementary Material 4.D)

Supplementary Material: indicator-level assessment
and line of sightFeasibility assessment approach

Sectoral indicators for 1.5°C-consistent pathways

Table 4.1

Illustrative model pathways: we still have a choice(High overshoot)Greenhouse gas emissions pathways•

Limiting warming to 1.5°C would require
systemic changes and CO2 removal
Energy systems transition
Land and ecosystems transition
Urban and infrastructure system transition
Industrial system transition

Carbon dioxide removal•Peter Essick / Aurora Photos

Mitigation and adaptation options within thesesystems transitions

Energy system transition•

In 1.5C-consistent pathways:
Lower energy use to meet energy demand
Fast electrification of energy end use
Renewables make up 70-85% of electricity in 2050
Coal makes up 0-2% of electricity in 2050
Increasingly feasible options: solar, wind,electricity storage
No similar improvement for options: nuclear, CCS

Peter Essick / Aurora Photos

Land and ecosystem transition•

In 1.5C-consistent pathways:
Large scale land-use and land cover transitions
Challenges for sustainable management of landdemandMitigation options: ecosystems restoration,
dietary shifts, efficient food production
Careful design and implementation of landbased mitigation options
Adaptation options: efficient livestock systems,
efficient irrigation, conservation agriculture
Changing agricultural practices as adaptation strategyPeter Essick / Aurora Photos

Industrial system transition•

In 1.5C-consistent pathways:
CO2 emissions 65-90% lower in 2050 (w.r.t. 2010)
Mitigation options: energy efficiency, electrification,hydrogen, bio-based feedstocks, CCUS
Increasing energy & process efficiency insufficient
Options technically proven at various scales but
barriers to large-scale deployment to be overcome

Peter Essick / Aurora Photos

Urban and infrastructure system transition•

In 1.5C-consistent pathways:
Energy demand in buildings 55-75% electricity in 2050
Share of low-emission final energy in transport sector
rises from <5% in 2020 to 35-65% in 2050
Mitigation options: electric vehicles, non-motorised
transport, low/zero-energy buildings
Adaptation options: green infrastructure,resilient water and urban ecosystem services
Potential for synergies between adaptation andmitigation optionsPeter Essick / Aurora Photos

Carbon Dioxide Removal (CDR) options considered in the
SR1.5
NaturalNatural &technologicalTechnological

Afforestation &reforestation

Bio-energy andCO2 capture andstorage (BECCS)

Enhanced
Weathering

Biochar
Soil Carbon
Sequestration

Direct Air CO2
Capture andStorage (DACCS)

BECCS and afforestation/reforestation included in modelled
pathways

Inspired by UNEP EGR 2017

CDR in SR1.5: Costs and 2050 potentials
300

Costs in $ tCO2-1

DACCS

200

100

0
1

2

3

Potentials in GtCO2 year -1

4

5

CDR in SR1.5: Costs and 2050 potentials
300

Costs in $ tCO2-1

DACCS

200

100
Biochar0
1

2

3

Potentials in GtCO2 year -1

4

5

CDR in SR1.5: Costs and 2050 potentials
300

Costs in $ tCO2-1

DACCS

200
BECCS

100
Biochar0
1

2

3

Potentials in GtCO2 year -1

4

5

CDR in SR1.5: Costs and 2050 potentials
300

Costs in $ tCO2-1

DACCS

200
BECCS

Enhanced
Weathering100
Biochar0
1

2

3

Potentials in GtCO2 year -1

4

5

CDR in SR1.5: Costs and 2050 potentials
300

Costs in $ tCO2-1

DACCS

200
BECCS

Enhanced
Weathering

100

Soil Carbon
Sequestration

Biochar0
1

2

3

Potentials in GtCO2 year -1

4

5

CDR in SR1.5: Costs and 2050 potentials
300

Costs in $ tCO2-1

DACCS

200
BECCS

Enhanced
Weathering

100

Soil Carbon
Sequestration

Biochar
Afforestation and Reforestation

0
1

2

3

Potentials in GtCO2 year -1

4

5

CDR in SR1.5: Side-effects
Included in pathways:•Bio-energy and CCS•Afforestation & reforestation

Other CDR:
•Direct Air Capture & Storage•Enhanced Weathering•Biochar•Soil Carbon Sequestration

GeophysicalSocio-cultural

Environmentalecologicalconfidence level

Institutional

options based on

Technological

Adaptation
optionEconomic

Selection of 9 examples ofConfidence

Illustrative Adaptation Feasibility Assessment
Context

Conservation
agriculture

MediumDepends on irrigated/rain-fed system, ecosystemcharacteristics, crop type, other farming
practices

Efficient
irrigation

MediumDepends on agricultural system, technology
used, regional institutional and biophysicalcontext

Efficient
livestocksystems

MediumDependent on livestock breeds, feed practices,and biophysical context (e.g. carrying capacity)

Communitybased
adaptation

MediumFocus on rural areas and combined withecosystems-based adaptation, does not include
urban settings

Ecosystem
restoration &avoideddeforestation

High

Mostly focused on existing and evaluated
Reducing Emissions from Deforestation andForest Degradation (REDD+) projects

Highfeasibility assessment

Coastaldefence &hardening

Depends on locations that require it as a first
adaptation option

MediumDepends on nature of planning systems andenforcement mechanisms

Out of 437 indicator-level

Sustainableland-use &urban
planning
Sustainablewater
management

High

Balancing sustainable water supply and risingdemand especiallyGreen
infrastructure& ecosystemservices

High

Depends on reconciliation of urban developmentwith green infrastructure•23 adaptation options•Based on 19 indicators insix dimensions
Total of 603 uniquereferences underpin theLand and Ecosystem Transitions

In Table 4.12:

assessments•37 NA; 36 LE; 36 NE

Urban and Infrastructure System
Transitions

adaptation options

dimensions
Total of 763 unique references

underpin the mitigation options
feasibility assessment
Out of 672 indicator-levelassessments:•38 NA; 67 LE; 101 NE

Land and
Ecosystem
Transitions•Based on 24 indicators in six

Urban and Infrastructure
System Transitions•28 mitigation options

Industrial System
Transitions

In Table 4.11:

Carbon Dioxide
Removalillustrative pathways

Energy System
Transitions

GeophysicalSocio-cultural

Environmentalecologicallevel and relevance toInstitutional

options based on confidence

Technological

Mitigation
OptionEconomic

Selection of 10 examples ofConfidence

Illustrative Mitigation Feasibility Assessment
Context

Solar PVHigh

Cost-effectiveness affected by solar irradiationand incentive regime. Also enhanced by legal
framework for independent power producers,which affects uptake.

Power sector
CCS

High

Varies with local CO2 storage capacity, presenceof legal framework, level of development andquality of public engagement

Ecosystems
restorationHigh

Depends on location and institutional factors

Electric cars
and buses

MediumVaries with degree of government intervention;requires capacity to retrofit “fuelling” stations

Nonmotorizedtransport

High

Viability rests on linkages with public transport,
cultural factors, climate and geography

Low/zeroenergy
buildings

High

Depends on size of existing building stock andgrowth of building stock

Energyefficiency

High

Potential and adoption depend on existing
efficiency, energy prices and interest rates, aswell as government incentives.

Industrial
CCUS

High

High concentration of CO2 in exhaust gas
improve economic and technical feasibility of
CCUS in industry. CO2 storage or reusepossibilities.

BECCS

MediumDepends on biomass availability, CO2 storage
capacity, legal framework, economic status andsocial acceptance

Afforestation&
reforestationHigh

Depends on location, mode of implementation,and economic and institutional factors

Enabling conditions

Enabling conditions
Widespread adoption of newtechnologies
National innovation policies andinternational cooperation
Technological innovation
capabilities (industry, finance)
Combination of public support for
R&D with policy mixes
incentivizing technology diffusion

Ashley Cooper / Aurora Photos

Enabling conditionsFirst time full assessment in an
IPCC report

Tailored to motivations,capabilities and resources
Public support and acceptability
Perceived fairness of the
distribution of consequences
and procedures

Ashley Cooper / Aurora Photos

Questions?
Q&A