(*) Former IPCC Vice-Chair ( )

Transcription

1 About the next IPCC Special Report : Global warming of 1.5 C ( ) in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty Jean-Pascal van Ypersele (*) & Philippe Marbaix Université catholique de Louvain (Belgium) Stakeholders Dialogue, CCPIE/CCIM, Brussels, 25 January 2018 (*) Former IPCC Vice-Chair ( ) Thanks to the Walloon government (funding the Walloon Platform for IPCC) for its support

2 Temperature spiral! Global Mean Temperature in C relative to ! Graph: Ed Hawkins (Climate Lab Book) Data: HadCRUT4 global temperature dataset! Available on

3 !"##$%&'()*($+)%$,)*,&%*$-$,./0'1&$,2'*3&$%/(4($$ 56'1$#./0'1&$#2'*3&$789:;$ +2 C +1.5 C ~pre-ind

4 Regional key risks and potential for risk reduction: Small Islands!"##$#% &'#(%)"%% *"+#)+,%+-$+#% IPCC, AR5, SYR, SPM 8

5 Global average! temperature! > 3m! ~3 C! Emissions! (all GHGs)! ~1.7 C! Sea-level! ~1.5m! < 1m! Source: adapted from Schae"er et al., Nature clim. chg. (2012)!

6 '??%)D/0'1&.E$C&1&%0/*&$3.)B'.$F'%0/*3$ observed # 2015! Based on IPCC AR5, Synthesis report (2014)!

7 The window for action is rapidly closing 65% of the carbon budget compatible with a 2 C goal is already used NB: this is with a probability greater than 66% to stay below 2 C Amount Remaining: Total Carbon Budget: 2900 GtCO 2 Amount Used : 1900 GtCO GtCO 2 NB: Emissions in 2011: 38 GtCO2/yr AR5 WGI SPM IPCC AR5 Synthesis Report

8 +%)0$12&$B'(&./*&$J$%&3'%C.&(($)+$12&$0/1/3'1/)*$3)'.$ >50% chance s <3 C likely <2 C Based on AR5 WGIII Figure 6.7

9 CO2eq Concentrations in 2100 (CO2 eq)! Category label! (conc. range)! Subcategories! Change in CO2eq emissions compared to 2010 (in %)! 2050! 2100! Temperature change in 2100 " - median climate sensitivity! Likelihood of staying below specific temperature levels (relative to = «#pre-industrial#»)! < 430! Only a limited number of individual model studies have explored levels below 430 ppm CO2eq! 450! ( )! Total range 1! -72 to -41! -118 to -78! ! Likely (66%) to stay below 2 C, # < 50% chances to stay below 1.5 C! 500! ( )! No overshoot of 530 ppm CO2eq! Overshoot of 530 ppm CO2eq! -52 to -42! -107 to -73! ! > 50% chances to stay below 2 C! -55 to -25! -114 to -90! ! About 50% chances to stay below 2 C! 550! ( )! No overshoot of 580 ppm CO2eq! Overshoot of 580 ppm CO2eq! -47 to -19! -81 to -59! ! -16 to 7! -183 to -86! ! Likely (66%) to stay below 3 C,! < 50% chances to stay below 2 C! ( )! Total range! -38 to 24! -134 to -50! ! Based WGIII table SPM.1 (incomplete : higher emissions scenarios not shown)

10 (Source: AR5 Synthesis report table 2.2)! <3 C! (see AR5 SYR)! possible?! implications?! ranges likely to change! at least due to more studies!

11 <0/((/)*($/*$(&,1)%(M$B'(&./*&($'*C$R$./4&.E$T$7U#$S$ baselines 2010 mitig.< 2C AR5 SYR figure SPM.14

12 UCL # 12 "'%/($'3%&&0&*1$ V! N%1/,.&$7M$!! 5W;$1)$(1%&*312&*$12&$3.)B'.$%&(?)*(&$1)$12&$12%&'1$)+$,./0'1&$,2'*3&X$/*$12&$,)*1&D1$)+$(@(1'/*'B.&$C&A&.)?0&*1$'*C$&++)%1($1)$ &%'C/,'1&$?)A&%1EX$/*,.@C/*3$BEM$!! Y).C/*3$12&$/*,%&'(&$/*$12&$3.)B'.$'A&%'3&$1&0?&%'1@%&$1)$F&..$ B&.)F$7$U#$'B)A&$?%&=/*C@(1%/'.$.&A&.($'*C$1)$?@%(@&$&++)%1($1)$./0/1$12&$1&0?&%'1@%&$/*,%&'(&$1)$9ZP$U#$'B)A&$?%&=/*C@(1%/'.$.&A&.(X$%&,)3*/H/*3$12'1$12/($F)@.C$(/3*/+/,'*1.E$%&C@,&$12&$%/(4($ '*C$/0?',1($)+$,./0'1&$,2'*3&[$$!!!*,%&'(/*3$12&$'B/./1E$1)$'C'?1$5W;$'*C$+)(1&%$,./0'1&$%&(/./&*,&$ '*C$.)F$3%&&*2)@(&$3'($&0/((/)*($C&A&.)?0&*1X$/*$'$0'**&%$ 12'1$C)&($*)1$12%&'1&*$+))C$?%)C@,1/)*[$$!! \'4/*3$+/*'*,&$+.)F($,)*(/(1&*1$F/12$'$?'12F'E$1)F'%C($.)F$ 3%&&*2)@(&$3'($&0/((/)*($'*C$,./0'1&=%&(/./&*1$C&A&.)?0&*1$

13 Global warming of 1.5 C A IPCC special report on the impacts of global warming of 1.5 C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty Proposed outline (as adopted in October 2016; report to be finalized in 2018) : Summary for policy makers (max 10 pages) Chapters : 1. Framing and context 2. Mitigation pathways compatible with 1.5 C in the context of sustainable development 3. Impacts of 1.5 C global warming on natural and human systems 4. Strengthening and implementing the global response to the threat of climate change 5. Sustainable development, poverty eradication and reducing inequalities Boxes (integrated case studies/regional and cross-cutting themes), FAQs (10 pages)

14 L.)B'.$F'%0/*3$)+$9ZPU#$ A IPCC special report on the impacts of global warming of 1.5 C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty Proposed outline (as adopted in October 2016; report to be finalized in 2018):! V! G@00'%E$+)%$?)./,E$0'4&%($50'D$98$?'3&(;$$ V! #2'?1&%($M$!! 9Z$]%'0/*3$'*C$,)*1&D1$!! 7Z$\/1/3'1/)*$?'12F'E($,)0?'1/B.&$F/12$9ZPU#$/*$12&$,)*1&D1$)+$(@(1'/*'B.&$ C&A&.)?0&*1$ Understanding 1.5 C; reference levels, probability,!! ^Z$!0?',1($)+$9ZPU#$3.)B'.$F'%0/*3$)*$*'1@%'.$'*C$2@0'*$(E(1&0($$!! _Z$G1%&*312&*/*3$'*C$/0?.&0&*1/*3$12&$3.)B'.$%&(?)*(&$1)$12&$12%&'1$)+$ */!and socio-economic opportunities and! %&',./0'1&$,2'*3&$$ Key!challenges! global and regional climate changes,!vulnerabilities, impacts, and risks at 1.5 C, taking#!! PZ$G@(1'/*'B.&$C&A&.)?0&*1X$?)A&%1E$&%'C/,'1/)*$'*C$%&C@,/*3$/*&I@'./1/&($ $CCurrent and emerging adaptation and account including adaptation negative potential emission ( )! V! `)D&($5/*1&3%'1&C$,'(&$(1@C/&(-%&3/)*'.$'*C$,%)((=,@11/*3$12&0&(;X$ V! ]Na($!transience, overshoot, stabilization ( )! Pathways compatible with 1.5 C compared with!2 C ( ) Technological, environmental, institutional!methodologies, & associated opportunities & Linkages!!challenges between ( ) achieving Case studies! SDGs and 1.5 C ( )!

15 1252*&/(6-7'),*+&"#*78/*'#$-/#/)7%7'")*"+*78/* ')7/)4/4*)%7'")%--9*4/7/&#')/4*:")7&'.67'")(*)%7'")%--9

16 ;"7%-*,-".%-*/#'(('")(* d)1'.$3.)b'.$&0/((/)*(m$_9ze$f$7zg$l1#h 7 $/*$789PX$_ei$)A&%$9ee8$ "&%,&*1'3&$.'*C=@(&$,2'*3&M$^ci$/*$9ec8X$ei$'A&%'3&C$788c=789P$ $ G)@%,&M$#j!N#[$Y)@321)*$&1$'.$7897[$L/3./)$&1$'.$789^[$k&$a@l%l$&1$'.$789c[$L.)B'.$#'%B)*$`@C3&1$789:$

17 Tentative and personal conclusions (The SR1.5 has not been finalized yet!) 1.5 C matters: reducing the warming, even by tenths of a C, can make large differences for impacts, as many of these are non-linear, that is they worsen faster with warming than the warming itself. The probability of extremes (heat waves, drought, floods, extreme sea level) is significantly lower in a 1.5 C world than in a 2 C world 1.5 C is much safer than 2 C in terms of longterm sea-level rise associated to ice-sheet processes, particularly for low-lying regions

18 Tentative and personal conclusions (The SR1.5 has not been finalized yet!) 1.5 C lower impacts will make adaptation less costly than in 2 C world, even if there is a temporary overshoot above 1.5 C It is very ambitious to reduce emissions fast enough to ZERO for a 1.5 C long-term average temperature above pre-industrial objective; a little easier with overshoot above 1.5 C for a short period The slower radical changes in emission patterns take place, the more we may need uncertain or risky technologies, such as large use of carbon dioxide removal from the atmosphere (possibly at the expense of bio-energy competition with food production) Decision making needs the best scientific information possible the IPCC SR 1.5 will be essential, but much can be done to raise ambition without waiting for it

19 Straks bij EPO (februari 2018) Voorwoord: Jill Peeters

20 G6.-'N*:8/A*O/*P"/:D* (6$N&'/6&Q* ":7".&/*12?3* *

21 Pour en savoir plus :!! : GIEC ou IPCC!! : beaucoup de mes dias!! : Plateforme wallonne pour le GIEC (e.a., Lettre d information)!! : réponses aux semeurs de doute!! Jean-Pascal van Ypersele (vanyp@climate.be)