IPCC:AR6/SR15/Chapter-2 - Revision history

Laura: /* Lead Authors */

2026-05-29T13:46:58Z

Lead Authors

← Older revision		Revision as of 13:46, 29 May 2026
Line 4,055:		Line 4,055:
	<span id="section-14"></span>		<span id="section-14"></span>
	<span id="lead-authors-1"></span>		<span id="lead-authors-1"></span>
	~~======~~ Lead Authors ~~======~~		'''Lead Authors'''

	* Luis Mundaca (Sweden, Chile)		* Luis Mundaca (Sweden, Chile)
Line 4,086:		Line 4,086:

	The use of the SCC for policy appraisals is, however, not straightforward in an SDG context. There are suggestions that a broader range of polluting activities than only CO <sub>2</sub> emissions, for example emissions of air pollutants, and a broader range of impacts than only climate change, such as impacts on air quality, health and sustainable development in general (see Chapter 5 for a detailed discussion), would need to be included in social costs (Sarofim et al., 2017; Shindell et al., 2017a)<sup>[[#fn:r557\|557]]</sup>. Most importantly, a consistent valuation of the SCC in a sustainable development framework would require accounting for the SDGs in the social welfare formulation (see Chapter 5).		The use of the SCC for policy appraisals is, however, not straightforward in an SDG context. There are suggestions that a broader range of polluting activities than only CO <sub>2</sub> emissions, for example emissions of air pollutants, and a broader range of impacts than only climate change, such as impacts on air quality, health and sustainable development in general (see Chapter 5 for a detailed discussion), would need to be included in social costs (Sarofim et al., 2017; Shindell et al., 2017a)<sup>[[#fn:r557\|557]]</sup>. Most importantly, a consistent valuation of the SCC in a sustainable development framework would require accounting for the SDGs in the social welfare formulation (see Chapter 5).
			</div>
			<span id="economic-and-investment-implications-of-1.5c-pathways"></span>

	~~<span id="economic-and-investment-implications-of-1.5c-pathways"></span>~~
	=== 2.5.2 Economic and Investment Implications of 1.5°C Pathways ===		=== 2.5.2 Economic and Investment Implications of 1.5°C Pathways ===

Laura: /* 2.5.1 Policy Frameworks and Enabling Conditions */

2026-05-29T13:46:37Z

2.5.1 Policy Frameworks and Enabling Conditions

← Older revision		Revision as of 13:46, 29 May 2026
Line 4,049:		Line 4,049:

	<span id="cross-chapter-box-5-economics-of-1.5c-pathways-and-the-social-cost-of-carbon"></span>		<span id="cross-chapter-box-5-economics-of-1.5c-pathways-and-the-social-cost-of-carbon"></span>
			<div class="container-box col-cross">

	== Cross-Chapter Box 5: Economics of 1.5°C Pathways and the Social Cost of Carbon ==		== Cross-Chapter Box 5: Economics of 1.5°C Pathways and the Social Cost of Carbon ==

Laura: /* Box 2.1 Bioenergy and BECCS Deployment in Integrated Assessment Modelling */

2026-05-29T13:44:44Z

Box 2.1 Bioenergy and BECCS Deployment in Integrated Assessment Modelling

← Older revision		Revision as of 13:44, 29 May 2026
Line 1,827:		Line 1,827:

	IAMs assume bioenergy to be supplied mostly from second generation biomass feedstocks such as dedicated cellulosic crops (for example ''Miscanthus'' or poplar) as well as agricultural and forest residues. Detailed process IAMs include land-use models that capture competition for land for different uses (food, feed, fiber, bioenergy, carbon storage, biodiversity protection) under a range of dynamic factors including socio-economic drivers, productivity increases in crop and livestock systems, food demand, and land, environmental, biodiversity, and carbon policies. Assumptions about these factors can vary widely between different scenarios (Calvin et al., 2014; Popp et al., 2017; van Vuuren et al., 2018)<sup>[[#fn:r296\|296]]</sup>. IAMs capture a number of potential environmental impacts from bioenergy production, in particular indirect land-use change emissions from land conversion and nitrogen and water use for bioenergy production (Kraxner et al., 2013; Bodirsky et al., 2014; Bonsch et al., 2014; Obersteiner et al., 2016; Humpenöder et al., 2018)<sup>[[#fn:r297\|297]]</sup>. The impact of bioenergy production on soil degradation is an area of active IAM development and was not comprehensively accounted for in the mitigation pathways assessed in this report (but is, for example, in Frank et al., 2017)<sup>[[#fn:r298\|298]]</sup>. Whether bioenergy has large adverse impacts on environmental and societal goals depends in large parts on the governance of land use (Haberl et al., 2013; Erb et al., 2016b; Obersteiner et al., 2016; Humpenöder et al., 2018)<sup>[[#fn:r299\|299]]</sup>. Here IAMs often make idealized assumptions about effective land management, such as full protection of the land carbon stock by conservation measures and a global carbon price, respectively, but variations on these assumptions have also been explored (Calvin et al., 2014; Popp et al., 2014a)<sup>[[#fn:r300\|300]]</sup>.		IAMs assume bioenergy to be supplied mostly from second generation biomass feedstocks such as dedicated cellulosic crops (for example ''Miscanthus'' or poplar) as well as agricultural and forest residues. Detailed process IAMs include land-use models that capture competition for land for different uses (food, feed, fiber, bioenergy, carbon storage, biodiversity protection) under a range of dynamic factors including socio-economic drivers, productivity increases in crop and livestock systems, food demand, and land, environmental, biodiversity, and carbon policies. Assumptions about these factors can vary widely between different scenarios (Calvin et al., 2014; Popp et al., 2017; van Vuuren et al., 2018)<sup>[[#fn:r296\|296]]</sup>. IAMs capture a number of potential environmental impacts from bioenergy production, in particular indirect land-use change emissions from land conversion and nitrogen and water use for bioenergy production (Kraxner et al., 2013; Bodirsky et al., 2014; Bonsch et al., 2014; Obersteiner et al., 2016; Humpenöder et al., 2018)<sup>[[#fn:r297\|297]]</sup>. The impact of bioenergy production on soil degradation is an area of active IAM development and was not comprehensively accounted for in the mitigation pathways assessed in this report (but is, for example, in Frank et al., 2017)<sup>[[#fn:r298\|298]]</sup>. Whether bioenergy has large adverse impacts on environmental and societal goals depends in large parts on the governance of land use (Haberl et al., 2013; Erb et al., 2016b; Obersteiner et al., 2016; Humpenöder et al., 2018)<sup>[[#fn:r299\|299]]</sup>. Here IAMs often make idealized assumptions about effective land management, such as full protection of the land carbon stock by conservation measures and a global carbon price, respectively, but variations on these assumptions have also been explored (Calvin et al., 2014; Popp et al., 2014a)<sup>[[#fn:r300\|300]]</sup>.
			</div>
	<div id="section-2-3-4-2"></div>		<div id="section-2-3-4-2"></div>

Line 1,915:		Line 1,915:
	<!-- END IMG -->		<!-- END IMG -->
	<span id="disentangling-the-whole-system-transformation"></span>		<span id="disentangling-the-whole-system-transformation"></span>

	== 2.4 Disentangling the Whole-System Transformation ==		== 2.4 Disentangling the Whole-System Transformation ==

Laura: /* 2.3.4.1 CDR technologies and deployment levels in 1.5°C pathways */

2026-05-29T13:44:14Z

2.3.4.1 CDR technologies and deployment levels in 1.5°C pathways

← Older revision		Revision as of 13:44, 29 May 2026
Line 1,818:		Line 1,818:

	<span id="box-2.1-bioenergy-and-beccs-deployment-in-integrated-assessment-modelling"></span>		<span id="box-2.1-bioenergy-and-beccs-deployment-in-integrated-assessment-modelling"></span>
			<div class="container-box col-regular">

	== Box 2.1 Bioenergy and BECCS Deployment in Integrated Assessment Modelling ==		== Box 2.1 Bioenergy and BECCS Deployment in Integrated Assessment Modelling ==

Laura: /* 2.2.2.2 CO 2 and non-CO 2 contributions to the remaining carbon budget */

2026-05-29T13:41:39Z

2.2.2.2 CO 2 and non-CO 2 contributions to the remaining carbon budget

← Older revision		Revision as of 13:41, 29 May 2026
Line 572:		Line 572:
	<!-- END TABLE -->		<!-- END TABLE -->

	# Chapter 1 has assessed historical warming between the 1850–1900 and 2006–2015 periods to be 0.87°C with a ±0.12°C likely (1-standard deviation) range, and global near-surface air~~<br />~~		# Chapter 1 has assessed historical warming between the 1850–1900 and 2006–2015 periods to be 0.87°C with a ±0.12°C likely (1-standard deviation) range, and global near-surface air temperature to be 0.97°C. The temperature changes from the 2006–2015 period are expressed in changes of global near-surface air temperature.
	temperature to be 0.97°C. The temperature changes from the 2006–2015 period are expressed in changes of global near-surface air temperature.
	# Historical CO <sub>2</sub> emissions since the middle of the 1850–1900 historical base period (mid-1875) are estimated at 1940 GtCO <sub>2</sub> (1640–2240 GtCO <sub>2</sub> , one standard deviation range) until end 2010. Since 1 January 2011, an additional 290 GtCO <sub>2</sub> (270–310 GtCO <sub>2</sub> , one sigma range) has been emitted until the end of 2017 (Le Quéré et al., 2018).		# Historical CO <sub>2</sub> emissions since the middle of the 1850–1900 historical base period (mid-1875) are estimated at 1940 GtCO <sub>2</sub> (1640–2240 GtCO <sub>2</sub> , one standard deviation range) until end 2010. Since 1 January 2011, an additional 290 GtCO <sub>2</sub> (270–310 GtCO <sub>2</sub> , one sigma range) has been emitted until the end of 2017 (Le Quéré et al., 2018).
	# TCRE: transient climate response to cumulative emissions of carbon, assessed by AR5 to fall likely between 0.8–2.5°C/1000 PgC (Collins et al., 2013), considering a normal distribution consistent with AR5 (Stocker et al., 2013). Values are rounded to the nearest 10 GtCO <sub>2</sub> .		# TCRE: transient climate response to cumulative emissions of carbon, assessed by AR5 to fall likely between 0.8–2.5°C/1000 PgC (Collins et al., 2013), considering a normal distribution consistent with AR5 (Stocker et al., 2013). Values are rounded to the nearest 10 GtCO <sub>2</sub> .
Line 583:		Line 582:

	<span id="overview-of-1.5c-mitigation-pathways"></span>		<span id="overview-of-1.5c-mitigation-pathways"></span>

	== 2.3 Overview of 1.5°C Mitigation Pathways ==		== 2.3 Overview of 1.5°C Mitigation Pathways ==

Laura at 13:39, 29 May 2026

2026-05-29T13:39:23Z

Show changes

Laura at 13:37, 29 May 2026

2026-05-29T13:37:34Z

Show changes

Laura at 08:23, 22 May 2026

2026-05-22T08:23:00Z

← Older revision		Revision as of 08:23, 22 May 2026
Line 1:		Line 1:
			{{ChapterNavigation
			\| cover = Cover-SR15.jpg
			\| reporturl = IPCC:AR6/SR15
			\| reporttitle = SR1.5
			\| prevurl = IPCC:AR6/SR15/Chapter-1
			\| nexturl = IPCC:AR6/SR15/Chapter-3
			}}

	= Chapter 2: Mitigation pathways compatible with 1.5°C in the context of sustainable development =		= Chapter 2: Mitigation pathways compatible with 1.5°C in the context of sustainable development =

Laura: Laura moved page IPCC:Sr15:Chapter:Chapter-2 to IPCC:AR6/SR15/Chapter-2 without leaving a redirect

2026-05-18T15:21:08Z

Laura moved page IPCC:Sr15:Chapter:Chapter-2 to IPCC:AR6/SR15/Chapter-2 without leaving a redirect

← Older revision	Revision as of 15:21, 18 May 2026
(No difference)

Laura: /* Supplementary Material */

2026-05-18T09:29:40Z

Supplementary Material

← Older revision		Revision as of 09:29, 18 May 2026
Line 4,323:		Line 4,323:

	<!-- START SM IMG -->		<!-- START SM IMG -->
	[https://www.ipcc.ch/site/assets/uploads/sites/2/2019/05/SR15_Chapter2_SM_Low_Res.pdf [[File:9413a859c42a258fe99760dd87f3967b Chapter-2-SM.jpg]]]		[https://www.ipcc.ch/site/assets/uploads/sites/2/2019/05/SR15_Chapter2_SM_Low_Res.pdf [[File:9413a859c42a258fe99760dd87f3967b Chapter-2-SM.jpg\|200px]]]

	To download the high res version of the Chapter 2 Supplementary Material [https://www.ipcc.ch/site/assets/uploads/sites/2/2019/05/SR15_Chapter2_SM_High_Res.pdf click here]		To download the high res version of the Chapter 2 Supplementary Material [https://www.ipcc.ch/site/assets/uploads/sites/2/2019/05/SR15_Chapter2_SM_High_Res.pdf click here]