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Sustain to gain: December 2012 Archives

Citizens of Europe enjoy high accessibility to energy efficient modes of transportation, such as public transit, and often can cycle safely in cities. Still, CO2 emissions in urban transport measure about two tons per capita each year even in well-designed cities such as Barcelona, Freiburg, Malmö, and Sofia. For ambitious mitigation these numbers need to be cut considerably. But automobile-centered structure of the periphery makes decarbonizing a daunting task. In a new study in Environmental Research Letters Creutzig and colleagues investigated possible options for reducing the CO2 emissions in urban transport of the four cities mentioned above.

A first look suggests that European fuel efficiency regulation already contribute their relevant bit: In BAU scenarios with relatively low additional demand (demography; trend in transport policies) more efficient cars due to suggested 2020 regulation will lower GHG emissions about 40% until 2040. But the ERL-study focused most on urban transport policies. These were clustered into three classes: "Pull" policies that attracted citizens into more efficient modes, such as tram-ways, bus rapid transit, and bicycles; "Push" measures that made the use of CO2 and energy intensive modes less attractive, e.g. reduced and more expensive parking space; and "Land-use" policies that enable the use of public transit and cycling by increasing accessibility on short-to-medium distances.

The study reveals that the combination of pull, push and land-use measures reduces CO2 emissions by an additional 40-70%, measured from the technology BAU scenario, and brings per capita emissions down to around 0.6t annually. The pull scenario brings only a small contribution, as many commuters prefer to stay in their cars. However, if push measures are added on the pull measures, a significant modal shift is expected: Car driving becomes more expensive, and additional space for walking, cycling and busses makes those modes even more attractive. Land-use measures such as densification and the prohibition of big boxes outside the city proper contributes a few more percentages to decarbonizing. This is particularly so in Malmö, a city that is in now in commuter distance to Copenhagen and is expected to grow considerably in population size. New medium-dense and transit-oriented development would make a huge difference here.

Crucially, the study demonstrates huge benefits in public health, and transport efficiency, accompanying such a decarbonizing strategy. Fuel spending would be reduced by billions of Euros annually, keeping more of spent income within city regions. Congestion would be reduced, enabling faster traffic for taxis and a down-scaled car fleet. At the same time, more cycling and walking would decrease coronary and other diseases, and cleaner air would improve well-being and reduce asthma incidents. 

The paper by Creutzig and colleagues highlights that decarbonization might be beneficial on a societal level, changing the debate of climate change mitigation from costs to benefits. It would be interesting to integrate such perspectives into conventional cost-focused studies of climate change mitigation.




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.

Climate change has for too long been regarded as a high-level abstract entity to be dealt with high-level policy instruments such as cap-and-trade. But climate change impacts real people, and it is time to bring action to those affected. No doubt, few things would be more effective than a tax or price on CO2 emissions (and this could easily be done in a revenue neutral way, for example reducing payroll taxes in return). But such a price instruments works on the margin, it ignores the stocks our society operates on, its infrastructure. We also need to make our infrastructures climateproof.

The hurricane exposed the weaknesses of existing infrastructures. Old above-ground transmissions lines went down, still leaving the poorer outskirts of New York, the commuter towns of New Jersey in a desperate situation. The backbone of New York transit was hit when the subway tunnels got flooded. As citizens reverted to cars, the city became clogged in congestion; gasoline shortages still impact many and endanger the most vulnerable. The hurricane effectively revealed inequality in infrastructure access - mirroring inequalities in income and wealth.

Fortunately, reshaping and reconfiguration of our infrastructures can reduce our carbon footprint, can increase our resilience to climate change, and improve the quality of everyone's life.

Let us take the example of urban transport. Here is a bold three-point transformation plan for New York:

First, make auto-mobility public. More than 95% of the time, cars are parking idly. That wastes much precious space in dense cities. Offering public cars, which can be accessed with smartphones and electronic IDs, saves parking space, and time for cruising. Significant resources can be saved on unnecessary car ownership. Cars would cease to be the default mobility option in cities, effectively reducing CO2 emissions. A car got crashed in an accident or in a hurricane? Public cars would provide collective insurance and guarantee accessibility. In rural or ex-urban areas, private cars would remain the predominant solution.

Second, improve infrastructure for cyclists. The Copenhagen example shows that expanding the bicycle network, and making it safe, can attract a huge number of users with modal shares exceeding 40%. Cycling is healthy and can make commuting a quality experience. E-bikes would enable routine 10 miles commutes. While cyclists also cause accidents, those accidents are less fatal, and cyclists cause neither air pollution nor noise nuisance. Cities become more livable. And cyclists are disaster resilient, as they neither need electricity nor gasoline.

Third, mass public transit should be put back into streets. Subways are incredibly expensive and remove citizens from daylight. Bus rapid transit and tram systems can be affordable even to tight municipal budgets. With pre-boarding ticketing and way of right, on-street public transit can speed up and carry high numbers of passengers. Bus rapid transit systems would also be more resilient to flooding, backing up more vulnerable subway tunnels.

Such a transformation is challenging, and politicians will struggle to address the concerns of many different constituencies. The barrier to this transformation is hardly a monetary one, but a question of leadership. But there are signs of hope that Bloomberg and other mayors can push us forward where federal government fails.