Human Settlements and Climate Change Mitigation: Key findings from the IPCC AR5 WG3 report

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1 Human Settlements and Climate Change Mitigation: Key findings from the IPCC AR5 WG3 report Shobhakar Dhakal, Coordinating Lead Author, IPCC AR5 WGIII Ch12 Associate Professor, Energy Field of Study Asian Institute of Technology

2 Contents Global and regional emission trends and needs for GHG mitigation Urbanization trends and GHG implications Urban mitigation options and barriers

3 A clear and up to date view of the current state of scientific knowledge relevant to climate change. The Working group I The Physical Science Basis 259 authors 39 countries 54,677 comments Working Group II Impacts, Adaptation and Vulnerability 309 authors 70 countries 50,444 comments Working Group III Mitigation of Climate Change 235 authors 57 countries 38,315 comments The Synthesis Report will be considered in Copenhagen in October 2014

4 Broader messages from IPCC WG III (mitigation) GHG emission growth have accelerated despite ongoing efforts Climate change mitigation, if unabated, would result into ⁰C world (which is undesirable) There is a significant shift in emission structure in recent decades regionally, along income groups, and sectors While mitigation challenges exist the low climate stabilization mitigation pathways are possible, options are there; delaying of mitigation would entail more costs and limit options But such pathways needs significant efforts from policies and institutions, investments and international cooperation

5 Chapter 12: Human Settlements, Infrastructure, and Spatial Planning IPCC reports are the result of extensive work from scientists around the world. 2 Coordinating Lead Authors 30 Authors 2 Review Editors 2 Chapter Science Assistants More than 110 pages Nearly 700 references More than 3,000 comments New chapter in AR5

6 GHG emissions growth between 2000 and 2010 has been larger than in the previous three decades. Based on Figure 1.3

7 About half of cumulative anthropogenic CO 2 emissions between 1750 and 2010 have occurred in the last 40 years. Based on Figure 5.3

8 Regional patterns of GHG emissions are shifting along with changes in the world economy. Based on Figure 1.6

9 Without additional mitigation, global mean surface temperature is projected to increase by 3.7 to 4.8 C over the 21 st century. Based on WGII AR5 Figure 19.4 Increase the likelihood of severe, pervasive, and challenging impacts Potential adverse impacts on agricultural production, extensive ecosystem impacts, and increasing species extinction risk (high confidence), possible crossing of thresholds that lead to disproportionately large earth system responses (low confidence)

10 Stabilization of atmospheric concentrations requires moving away from the baseline regardless of the mitigation goal. Based on Figure 6.7

11 Stabilization of atmospheric concentrations requires moving away from the baseline regardless of the mitigation goal. ~3 C Based on Figure 6.7

12 Urbanisation For most of human history: The world population mostly lived in rural areas and in small urban settlements, and growth in global urban population occurred slowly 1800: World population was around one billion, only 3% of the total population lived in urban areas and only one city Beijing had had a population greater than one million (Davis, 1955; Chandler, 1987; Satterthwaite, 2007) 1900: Global share of urban population was about 13% 1950: 29% ; % (UN DESA, 2012) 1960: Global urban population surpassed one billion (UN DESA, 2012) It took only additional 26 years to reach two billion; time for additional billion is decreasing Today, approximately 52% of the global population, or 3.6 billion, are estimated to live in urban areas (UN DESA, 2012).

13 Urbanization is associated with increases in income and higher urban incomes correlated with higher energy and GHG emissions Urbanization rates in developed regions are higher compared to Asia and Africa, but developing regions are catching up The overall share developed and developing regions in the global urban population have gone through a structural change in recent decades

14 Urban Population Shares of Regions UN DESA, 2012; IPCC 2014

15 Urban areas account for between 71% and 76% of CO2 emissions from global final energy use and between 67-76% of global energy use Source: GEA, 2012; Grubler et al., 2012) Cities in non-annex I countries have generally higher per capita final energy use and GHG emissions than national averages

16 No single factor explains variations in per-capita emissions across cities, and there are significant differences within and across countries Influenced by a variety of physical, economic and social factors, development levels, and urbanization histories specific to each city Key factors include: income, population dynamics, economic structure urban form, locational factors choice of energy sources, mobility and housing infrastructure, technology and lifestyle Key urban form drivers of energy and GHG emissions are density, land use mix, connectivity and accessibility

17 Urban population and urban land is expected to expand further Expansion of urban areas is taking place at twice the rate of urban population growth Global rural population will decline soon and all population growth will be in urban Between 2000 and 2030, urban areas will expand between 0.3 million to 2.3 million km2 (56-310%) - 55% of the total urban land in 2030 is expected to be built in the first three decades of the 21st century Nearly half of the global growth in urban land cover is forecasted to occur in Asia; 55% of the regional growth to take place in China and India Schneider et al., 2009; Angel et al., 2011; Seto et al., 2011, 2012

18 The next two decades present a window of opportunity for mitigation as a large portion urban areas will be developed during this period The kinds of towns, cities, and urban agglomerations that ultimately emerge over the coming decades will have a critical impact on energy use and carbon emissions Two sources of emissions: Construction of infrastructure and buildings (stock), usage of infrastructure and buildings (flow) Problem Lock-in : Long life of infrastructure and built environment determines energy and emissions pathways including lifestyles and consumption patterns UN DESA, (2010), GEA (2012)

19 Future infrastructure emissions alone could require about a third of the 2 C emission budget. Total CO 2 emissions (per capita) needed to build up today s infrastructure Future CO 2 emissions if developing countries catch up to average developed country level. The existing infrastructure stock of the average Annex I resident is 3 times that of the world average and about 5 times higher than that of the average non-annex I resident The build-up of massive infrastructure in developing countries will result in significant future emissions Müller et al., 2013

20 Key drivers for emissions from urban form are density, land use, connectivity and accessibility. Higher density leads to less emissions (i.a. shorter distances travelled). Mix of land-use reduces emissions. Improved infrastructural density and design (e.g. streets) reduces emissions. Accessibility to people and places (jobs, housing, services, shopping) reduces emissions. Numbers from Ewing and Cervero (2010), National Research Council (2009a), and Salon et al (2012) are based on the following original sources: Density (Schimek, 1996; Kockelman, 1997; Sun et al., 1998; Pickrell and Schimek, 1999; Ewing and Cervero, 2001; Holtzclaw et al., 2002; Bhatia, 2004; Boarnet et al., 2004; Bento et al., 2005; Zhou and Kockelman, 2008; Fang, 2008; Kuzmyak, 2009a; a; Brownstone and Golob, 2009; Ewing et al., 2009; Greenwald, 2009; Heres-Del-Valle and Niemeier, 2011); Land Use (Kockelman, 1997; Sun et al., 1998; Pushkar et al., 2000; Ewing and Cervero, 2001, 2010; Chapman and Frank, 2004; Frank and Engelke, 2005; Kuzmyak et al., 2006; Vance and Hedel, 2007; Brownstone and Golob, 2009; Kuzmyak, 2009b; Frank et al., 2009); Connectivity (Ewing and Cervero, 2001; Boarnet et al., 2004; Chapman and Frank, 2004; Frank and Engelke, 2005; Ewing et al., 2009; Greenwald, 2009; Frank et al., 2009); Accessibility (Goodwin, 1996; Ewing et al., 1996, 2009; Kockelman, 1997; Cervero and

21 Low carbon cities need to consider urban land use mix Density is necessary but not sufficient condition for lowering urban emissions Adapted from (Cheng, 2009) Manaugh and Kreider, 2013

22 The largest mitigation opportunities with respect to human settlements are in rapidly urbanizing areas with - Small and mid-size cities - Developing regions of the world - Economical growing regions - Infrastructure is being built and yet not locked-in But these are often the places where limited financial and institutional capacities persist

23 The feasibility of spatial planning instruments for climate change mitigation is highly dependent on a city s financial and governance capability Sources: Bahl and Linn (1998); Bhatt (2011); Cervero (2004); Deng (2005); Fekade (2000); Rogers (1999); Hong and Needham (2007); Peterson (2009); Peyroux (2012); Sandroni (2010); Suzuki et al. (2013); Urban LandMark (2012); U.S. EPA (2013); Weitz (2003).

24 Thousands of cities are undertaking Climate Action Plans and mitigation commitments Little systematic assessment on their implementation & the extent to which reduction targets are being achieved or emissions reduced Focus largely on energy efficiency Sources: Baseline emissions, reduction targets, and population from self-reported data submitted to Carbon Disclosure Project (2013). GDP data from Istrate & Nadeau (2012). Note that the figure is illustrative only; data are not representative, and physical boundaries, emissions accounting methods and baseline years vary between cities. Many cities have targets for intermediate years (not shown). Yet, their aggregate impact on urban emissions is uncertain Limited consideration to land use planning strategies and other cross sectoral measures

25 In decisions making, the policy leverages do not often match with the largest mitigation opportunities Source: synthesized from (Jaccard et al., 1997; Grubler et al., 2012) Systemic changes have more mitigation opportunities but hindered by policy fragmentation

26 Successful implementation of urban-scale climate change mitigation strategies can provide health, economic and air quality co-benefits Urban areas continue to struggle with challenges, including ensuring access to energy, limiting air and water pollution, and maintaining employment opportunities and competitiveness Action on urban-scale mitigation often depends on the ability to relate climate change mitigation efforts to local co-benefits

27 Mitigation can result in large co-benefits for human health and other societal goals. Based on Figures 6.33 and 12.23

28 Governance paradox and need for a comprehensive approach Systemic changes in urban areas have large mitigation opportunities but hindered by current patterns of urban governance, policy leverages and persisting policy fragmentation Governance and institutional capacity are scale and income dependent, i.e., tend to be weaker in smaller scale cities and in low income/revenue settings However, the bulk of urban growth momentum is expected to unfold in small- to medium-size cities in non-annex-i countries The largest opportunities for GHG emission reduction might be precisely in urban areas where governance and institutional capacities to address them are weakest The feasibility of spatial planning instruments for climate change mitigation is highly dependent on a city s financial and governance capability For designing and implementing climate policies effectively, institutional arrangements, governance mechanisms, and financial resources all should be aligned with the goals of reducing urban GHG emissions

29 Urban population in Nepal 5 mn UN DESA, 2012

30 Implications to Nepal (personal perspectives) Nepal is rapidly urbanizing and infrastructures are being built- can we avoid locking-in urban development in Nepal into carbon intensive pathways? What are the options and leverages? Does Nepal need a new guidance policy new urbanization? What is the vision/goal/approaches for climate compatible urban development in Nepal? Are spatial aspects such as better urban form being adequately considered in planning in Nepal?

31 Implications to Nepal (personal perspective) How to enhance the capacity and resource leveraging for urban development? How to optimize co-benefits of urban GHG mitigation (air pollution reduction, better access to mobility, housing and infrastructure, renewable system etc) in Nepal? How to ensure better urban governance and address policy fragmentation in Nepal? How to approach/channel climate-related existing local and international financial and technology mechanisms to benefit urban development in Nepal

32 For further information

33 Knowledge gaps 1. Lack of consistent and comparable emissions data at local scales 2. Little scientific understanding of the magnitude of the emissions reduction from altering urban form, and the emissions savings from integrated infrastructure and land use planning. 3. Lack of consistency and thus comparability on local emissions accounting methods 4. Few evaluations of urban climate action plans and their effectiveness. 5. Lack of scientific understanding of how cities can prioritize climate change mitigation strategies, local actions, investments, and policy responses that are locally relevant 6. Large uncertainties as to how urban areas will develop in the future

34 Key characteristics of the scenarios collected and assessed for WG3 AR5

35 Stringent mitigation involves substantial upscaling of lowcarbon energy. Rapid improvements of energy efficiency A tripling to nearly a quadrupling of the share of zero- and low-carbon energy supply from renewables, nuclear energy and fossil energy with carbon dioxide capture and storage (CCS), or bioenergy with CCS (BECCS) by the year scenarios typically rely on the availability and large-scale deployment of carbon dioxide removal technologies, but both are uncertain

36 Global costs rise with the ambition of the mitigation goal but do not strongly affect global GDP growth Estimates do not include the benefits of reduced climate change as well as co-benefits and adverse side-effects of mitigation Based on Table SPM.2

37 Mitigation cost (median) for 450 ppm scenario: Do not strongly affect global GDP growth GDP GDP without mitigation GDP with stringent mitigation (reaching 450 ppm CO2eq in 2100) Loss in global consumption in 2030: 1.7% (median) Loss in global consumption in 2050: 3.4% (median) Loss in global consumption in 2100: 4.8% (median) Current Time

38 Delaying mitigation is estimated to increase the difficulty and narrow the options for limiting warming to 2 C. delayed mitigation immediate action

39 Delaying mitigation is estimated to increase the difficulty and narrow the options for limiting warming to 2 C.

40 Delaying mitigation is estimated to increase the difficulty and narrow the options for limiting warming to 2 C. Based on Figures 6.32 and 7.16