CLIMATE CHANGE 2014 - NordGen · 2014. 9. 16. · Bioenergy with CCS and/or afforestation are important in many low emission scenarios (CH6). Land use change associated with bioenergy

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CLIMATE CHANGE 2014CLIMATE CHANGE 2014Mitigation of Climate ChangeMitigation of Climate Change

Working Group III contribution to the IPCC Fifth Assessment Report


WG I – Recap: The slow and the fast domain of the global carbon cycle

Fig FAQ 6.1 (SOD)


Carbon Cycle Basics

“During the Holocene (beginning 11,700 years ago) prior to the Industrial Era the fast domain was close to a steady state, as evidenced by the relatively small variations of atmospheric CO2 recorded in ice cores (see Section 6.2), despite small emissions from human-caused changes in land use over the last millennia (Pongratz et al., 2009).” (AR5 WGI CH 6.1.1.1)

Fossil fuel extraction from geological reservoirs, and their combustion, has resulted in the transfer of significant amount of fossil carbon from the slow domain into the fast domain, thus causing an unprecedented, major human-induced perturbation in the carbon cycle” (AR5 WGI CH6.1)


Global Carbon Stocks and flows ( fig 6.1 WG I AR5)

Black:Flux : Pre 1750 (annual)Stock: Pre 1750 Level

Red: Flux : 2000-09 ( avg.annual) Stocks: Change since 1750


Global Carbon Stocks and flows ( fig 6.1 WG I AR5)

Black:Flux : Pre 1750 (annual)Stock: Pre 1750 Level

Red: Flux : 2000-09 ( avg.Annual) Stocks: Change since 1750


The division of labor between climate models and integrated assessment models

Figure from Presentation on Scenarios by JAE EDMONDS, RICHARD MOSS, BRIAN O’NEILL, DETLEF VAN VUUREN, JOHN WEYANT, August 12, 2013


Stabilizing greenhouse gas (GHG) concentrations will require large‐scale transformations in human societies, from the way that we produce and

consume energy to how we use the land surface (ES CH6)

Figure SPM.4. (upper panel) Pathways of global GHG emissions (GtCO2eq/yr) in baseline and mitigation scenarios for different long-term concentration levels


Cumulative total emissions of CO2 and global mean surface temperature response are approximately linearly related (SPM)

Net CO2 emissions from land‐use (also referred to as ‘net AFOLU CO2 emissions, see Figure 6.5) result from an interplay between the use of land to produce food and other non‐energy products, to produce bioenergy, and to store carbon in land (CH 6.3.2.4)


Mitigation scenarios indicate a potentially critical role for land-related mitigation measures (TS.3.1.2)10Mkm2 = 1000Mha


Scenarios from integrated models suggest the possibility of very different landscapes relative to today, even in the absence of mitigation (6.3.5)


Bioenergy with CCS (BECCS) are important in many low emission scenarios


Most scenarios show declining CO2 emissions from land‐use as a result of declining deforestation rates, both with and without mitigation (CH 6.3.2.4)

Figure 6.10. Right Panel Only: Net AFOLU CO2 emissions in mitigation scenarios. The right panel shows net CO2 emission from land use as function of time. Source: WG III AR5 Scenario Database (Annex II.10).


Combining bioenergy with CCS (BECCS) offers the prospect of energy supply with large‐scale net negative emissions which plays an important role in many low‐stabilization scenarios, while it entails challenges and risks (SPM 4.2.2)

Figure 11.22. Illustration of the sum of CO2-equivalent (GWP100) emissions from the process chain of alternative transport and power generation technologies both with and without CCS.


Most studies agree that the technical potential for bioenergy in 2050 is at least approximately 100 EJ/yr (Sec 11.13.2)


Mitigation costs for low emission pathways are estimated to increase by 44-77% if the availability of modern bioenergy is limited to 100 EJ/yr (Tab. SPM 2)

Many models could not achieve atmospheric concentration levels of about 450 ppm CO2eq by 2100 if additional mitigation is considerably delayed or under limited availability of key technologies, such as bioenergy, CCS, and their combination (BECCS). (SPM)


The most cost-effective mitigation options in forestry are afforestation, sustainable forest management and reducing deforestation, with large differences in their relative importance across regions (SPM 4.2.4 – WG III)

CH 11. 3.1 Supply side options - Tab 11.2 (section)


Non‐permanence/reversibility (CH 11.3.2): Reversals are the release of previously sequestered carbon, which negates some or all of the benefits from sequestration that has occurred in previous years. This issue is sometimes referred to as ‘non‐permanence’ (Smith, 2005) . Various types of carbon sinks (e.g., afforestation/reforestation, agricultural soil C) have an inherent risk of future reversals.

Saturation (CH 11.3.2):Substitution of fossil fuel and material with biomass, and energy‐intensive building materials with wood can continue in perpetuity.

In contrast, it is often considered that carbon sequestration in soils (Guldea et al., 2008) or vegetation cannot continue indefinitely.

The carbon stored in soils and vegetation reaches a new equilibrium (as the trees mature or as the soil carbon stock saturates). As the soils/vegetation approach the new equilibrium, the annual removal (sometimes referred to as the sink strength) decreases until it becomes zero at equilibrium. This process is called saturation (Smith, 2005; Körner, 2006, 2009; Johnston et al., 2009b)

Interplay between adaption and mitigation (SPM 4.2.4):Policies governing agricultural practices and forest conservation and management are more effective when involving both mitigation and adaptation. Some mitigation options in the AFOLU sector (such as soil and forest carbon stocks) may be vulnerable to climate change.

Understanding Reversibility and Saturation is important for Assessing Mitigation Effectiveness of C-Storage (see)


Main Drivers of Climate Changefig 1.1 in 5AR WGI


Land use and land use changes involve interactions with the climate system through many complex mechanisms

Land use change associated with bioenergy expansion, afforestation or deforestation can affect GHG balances, albedo and other climate drivers in several ways (ES CH11 AFOLU)

Figure from: Jackson et al., Env. Res. Lett., (2008)


In the year 2000, almost one quarter of the global terrestrial net primary production (one third of the above‐ground part) was ‘appropriated’ by humans. (From section 11.4.1)

This means that it was either lost because the net primary productivity (the biomass production of green plants, net primary production, NPP) of agro-ecosystems or urban areas was lower than that of the vegetation they replaced or it was harvested for human purposes, destroyed during harvest or burned in human‐induced fires (Imhoff et al., 2004; Haberl et al., 2007).

Figure 1 in :


Good and well informed land management is essential to ensure a balance of multiple ecosystem services

Any large-scale change in land use, for biomass for energy, or for sequestration in vegetation, will likely increase the competition for land, water, and other resources, and conflicts may arise with important sustainability objectives such as food security, soil and water conservation, and the protection of terrestrial and aquatic biodiversity

ES AFOLU CH11


The Land ChallengeStabilizing greenhouse gas (GHG) concentrations will require large‐scale transformations in human societies, from the way that we produce and consume energy to how we use the land surface (ES CH6)

Scenarios from integrated models suggest the possibility of very different landscapes relative to today, even in the absence of mitigation (6.3.5)

Bioenergy with CCS and/or afforestation are important in many low emission scenarios (CH6).

Land use change associated with bioenergy expansion, afforestation or deforestation can affect GHG balances, albedo and other climate drivers in several ways (ES CH11 AFOLU)

Good and well informed land management is essential to ensure a balance of multiple ecosystem services including biodiversity

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CLIMATE CHANGE 2014 - NordGen · 2014. 9. 16. · Bioenergy with CCS and/or afforestation are important in many low emission scenarios (CH6). Land use change associated with bioenergy