by Dave Elliott
In my last post, I looked at how cities would have to rely in part on imported green power, given their spatial constraints and high energy use, if they want to be fully sustainable. That may worry some environmentalists. It also has social implications for cities and for rural areas, and their interactions, as I will explore in this post. (more…)
By Felix Creutzig
Last week’s hurricane, humanized as Sandy, crashed the East Coast, killed more than 100 people and injured many more. Lower Manhattan got flooded, and New Jersey still looks like a disaster zone that we were used to see from the distant places such as the Caribbean islands. Our infrastructures are neither resilient to climate change, nor helpful in reducing our greenhouse gas emissions.
There is no doubt that human-made climate change systemically caused this extremely powerful and unusual hurricane. Atlantic water temperature considerably exceeded its long-term average and the melting of Arctic ice produced a high-pressure system pushing the Hurricane to the most densely populated area of North America. The scary news is that hurricane Sandy won’t be the exception. Climate change is happening and our action will determine whether such storms hit our coasts annually or only every other decade.
By Felix Creutzig
In a recent blog, I discussed an article. The paper points out that urban form policies have a rather moderate impact as population growth and land consumption trends dominate the overall dynamics. In my blog I suggested that EU fuel efficiency regulation for new cars should demonstrate higher impacts on reducing GHG emissions. Anil Namdeo from the author team responds with the following reply:
“The Trend trajectories are largely driven by the high rate of growth in the region (London and South East): the number of dwellings increase by 30% over the Trend, a product of a 19.1% growth in population and a reduction in household size. Road traffic grows from 220 billion vehicle kms in 1997, to 338 billion vehicle kms in 2031, an increase of some 1.57% per annum. This growth eventually counteracts the gains in noxious emission (NOX, PM10, CO, VOC) reduction won via clean technology. Although newer vehicles will be more fuel efficient, CO2 emissions continue to rise because of the growth in vehicle travel and the increase in congestion and because we have not assumed carbon neutrality for new dwellings as these have yet to be achieved in mass market building. The lower speeds associated with congestion create additional emissions due to frequent stop-start operation of vehicles.”
From my point of view, this discussion demonstrates that urban form measures are insufficient on their own to achieve ambitious GHG abatement and other environmental targets. Instead, I argue that a combination of land use, push and pull policies can achieve synergies resulting into a relatively low-carbon urban transport world.
By Felix Creutzig
“Does urban form really matter?” This is the subtitle of a paper by Echenique et al., just published in the Journal of the American Planning Association.
The paper scrutinizes the claim that compaction makes cities more sustainable. Starting point is the finding of the US Commission of Integrated Transport (2009) that compaction has a modest effect in reducing vehicle travel. Echenique et al. posit that the social and economic costs needs to be treated comprehensively. Using modifications of the advanced transport-land-use model software MEPLAN, the authors model the impact of three different land-use developments in three English regions/cities, identifying 26 sustainability indices. The three developments are labeled dispersal, planned expansion, and compaction. Compaction reduces CO2-emissions from buildings and transport only between 1–5% compared with the dispersal scenario running from
1997 to 2031. Moreover, the differences in land-use due to spatial configurations are small compared to the impact of socioeconomic change and population growth.
By Felix Creutzig
Walking and cycling dominate urban transport in Asia and Africa. This statement is worth repeating. Walking and cycling dominate urban transport in Asia and Africa. It is one of the key statements in the book “Urban Transport in the Developing World“, subtitled “A Handbook for Policy and Practice”, edited by Harry Dimitriou and Ralph Gakenheimer. But it is much more than a handbook. It is the most comprehensive overview on the topic. With more than 600 pages, take your time reading it. While there is some redundancy, reading this book carefully will provide you with a superb, encompassing understanding of urban transport in the developing world.
Here is the book’s story. 60% of the world’s population live in Asia, and Asia is the epicenter of the global urbanization wave. Asia is also the focal point of incredible motorization with China alone being projected to have in 2050 nearly as many cars, as the world has currently on its roads, in totol: 700 million cars. An Asian city also gives its name to one of the key concepts I extracted from the book: the Bangkok syndrome. Similar to their OECD counterparts, Asian and African cities start with dense, walkable city cores. At the beginning of the last century, OECD cities invested in the then upcoming rail-based transport infrastructure, shaping cities profoundly. With the relatively slow but profound rise of automobility, American cities developed into low-density automobile cities, while European cities kept their inner cities served with public transit. Asian and African cities seem to be mostly on a different trajectory: They skip the stage of public transport infrastructures and move directly into individualized motorized mobility. This is too some degree quite surprising: Relative to their GDP, cities of the developing world invest much more into highways, citizens proportionally much more into personal transport than their OECD counterparts do and have done (see e.g. Jeffrey Kenworthy’s contribution). Inversely, these developing cities have high population density and are unsuitable for car transport. As a result, especially Asian cities develop into ‘motorcycle’ cities (Barter, 2000): motorized two-wheelers are best adapt to navigate the traffic disasters, but are subject to high accident rates and still face congestion.
Distribution and accessibility is another, related theme that develops continously across chapters. As the introductary statement indicates, paraphrased from Setty Pendakur’s chapter, non-motorized transport is the starting point of analysis, for transport efficiency and transport equity matters alike. Urban transport planning is often technocratically framed as ‘apolitical intervention’ (Eduardo Vasconcellos), where in fact it is top income segment who by driving their cars consume 10 times more space than the urban poor, consume a largest part of transport energy, and are responsible for most of street-level air pollution. It is then quite clear that a suitable normative objective for urban transport is reasonable accessibility for all, possibly emphasizing the urban poor (the concept itself actually may need to be qualified, see Xavier Godard’s chapter). Accesssibility itself is a highly interesting concept: Some cities, such as Dakar, seem to have high accessibililty – walkability – for the poorest quantile. In contrast, in cities like Buenos Aires the lowest income quintile pays proportionally to income much more than the richest quantile. Poverty may also directly reduce social contact by rendering visits to family or friends infeasible.
In line of the this comprehensive analysis, it then follows naturally to require comprehensive assessments of urban transport projects and plans, relying on strategic environmental assessments (Michael Replogle), inclusive equity evaluation (Eduardo Vasconcellos), and context-specific economic appraisal (Walter Hook). The key conundrum, however, is then in the meta-level of institions (Elliott Sclar and Julie Touber). In the dense urban environment of Asian and many African cities, the traffic disaster of the Bangkok syndrome can only be tackled with efficient public transport. But public transport can be regarded as a quasi-public good, and will not emerge from demand-side focussed market outcomes. Hence institutional capacity, a governance framework of promoting public goods and better public transport and non-motorized transport system need to coevolve simultenously. Transport planning alone is not enough.