Mitigation of Climate Change Key Insights from IPCC AR5. Keywan Riahi International Institute for Applied Systems Analysis

Transcription

1 Mitigation of Climate Change Key Insights from IPCC AR5 Keywan Riahi International Institute for Applied Systems Analysis Osterreichische Akademie der Wissenschaften Wien, 24 November 2014

2 GHG emissions growth has accelerated despite reduction efforts.

3 Most emission growth is CO 2 from fossil fuel combustion. 3

4 About half of cumulative anthropogenic CO 2 emissions between 1750 and 2010 have occurred in the last 40 years. 4

5 There is far more carbon in the ground than emitted in any baseline scenario. 5

6 Limiting warming to 2 C involves substantial technological, economic and institutional challenges.

7 Without additional mitigation, GHG emissions continue to increase by a factor of about two compared to today. 7

8 Without additional mitigation, global mean surface temperature is projected to increase by 3.7 to 4.8 C over the 21 st century. Baselines 8

9 Stabilization of atmospheric concentrations requires moving away from the baseline regardless of the mitigation goal. ~ 3ᵒC 9

10 Stabilization of atmospheric concentrations requires moving away from the baseline regardless of the mitigation goal. ~ 3ᵒC 10

11 Mitigation involves substantial upscaling of low-carbon energy. ~ 2ᵒC 11

12 Mitigation involves substantial upscaling of low-carbon energy. ~ 2ᵒC ~ 3ᵒC 12

13 Actions over the next 5-15 years will be critical

14 Delaying mitigation increases the difficulty and narrows the options for limiting warming to 2 C. 14

15 Delaying mitigation increases the difficulty and narrows the options for limiting warming to 2 C. 15

16 Delaying mitigation increases the difficulty and narrows the options for limiting warming to 2 C. 16

17 Delaying mitigation increases the difficulty and narrows the options for limiting warming to 2 C. 17

18 Delaying mitigation increases the difficulty and narrows the options for limiting warming to 2 C. 18

19 Delaying mitigation is estimated to increase the difficulty and narrow the options for limiting warming to 2 C. Sweden & France after the oil crisis 19

20 Delaying mitigation is estimated to increase the difficulty and narrow the options for limiting warming to 2 C. Collapse of the former Soviet Union Europe WWI & II (>4%) 20

21 Delaying mitigation increases the difficulty and narrows the options for limiting warming to 2 C. 21

22 Delaying mitigation increases the difficulty and narrows the options for limiting warming to 2 C. The Cancun Pledges are inconsistent with reaching 2C 22

23 Reaching low stabilization requires rapid decarbonization of energy supply + efforts across all sectors

24 Mitigation requires changes throughout the economy. Efforts in one sector determine mitigation efforts in others. 24

25 Mitigation requires changes throughout the economy. Efforts in one sector determine mitigation efforts in others. 25

26 Mitigation requires changes throughout the economy. Efforts in one sector determine mitigation efforts in others. 26

27 Decarbonization of energy supply is a key requirement for stabilizing atmospheric CO 2 eq concentrations below 580 ppm. 27

28 Decarbonization of energy supply is a key requirement for stabilizing atmospheric CO 2 eq concentrations below 580 ppm. 28

29 Achieving low stabilization requires substantial investments, which can lead to co-benefits for other local or national policy objectives

30 Substantial reductions in emissions would require large changes in investment patterns and appropriate policies. 30

31 Sustainable development means overcoming several energy challenges Energy Poverty Energy Security Land Use & Forests Climate Change Water Air Pollution Image sources: NASA,

32 Mitigation can result in large co-benefits for human health and other societal goals. 32

33 Mitigation can help to reduce energy security concerns

34 Integration across climate and other objectives is key for costeffectivly addressing environmental challenges

35 Kromp-Kolp, Nakicenovic, Steininger et al, 2014 APCC-AAR14: Austria in the context of global climate change With substantial mitigation Change in average surface temperature in case of high emissions ( to )

36 Thank you! IIASA-IPCC database: