Andreas Schafer, director of the Martin Center for Architectural and Urban Studies at the University of Cambridge, discusses the impact of the transportation sector with respect to climate destabilisation (change) and growing carbon emissions. Specifically he talks about the specific factors at play including passenger kilometres travelled (PKT), energy intensity per PKT and emissions intensity of given fuels with data for various countries at differing stages of economic prosperity. Andreas finds a lot of commonality between the amount of time different countries populations spend travelling and the proportion of GDP they spend doing so.
While there are vast differences in emissions impact between countries they all seem to follow a similar trend as they develop, it’s just where they lie on that curve. As people get richer they generally spend more on faster modes of transport (walking > bike > car > train > plane/high speed rail) and cover more kilometres/miles. This is compounded by the fact that as countries get richer, there has been a tendency for more women in the workforce which has resulted in less children and lower occupancy rates in vehicles (as well as more money to spend on travel). The existing trends for energy intensity are also heading in the wrong direction becoming higher and not lower. The gains made in engine efficiency have been more than offset by larger, faster and more powerful vehicles and the example of Toyota Camry has shown that 24 years of advancement has resulted in a 20% increase in fuel use. He also quickly summarises the relative carbon intensity of various fuel/vehicle combinations although most of the alternative fuels are a long way away from being at the scale our current conventional oil fuels are used.
Andreas then looks to the future to see what the potential impact policies can help to guide technology and social/behavioural patterns into creating a sustainable transport systems. In short, with the most effective policies in place we might be able to reduce emissions intensity of the worldwide by 30-50%, the impact of massive populations of the emerging countries such as China behaving more like western countries is likely to lead to at best a doubling of emissions from transport. Without these policies it could be 3 to 4 times more than today.
For a link to his co-authored official work – Transportation in a Climate-Constrained World – and raw data from some of his slides please visit www.transportandclimate.com