2007: IPCC AR4 Chapter 5: Transport and its Infrastructure


2007This chapter, written before the electric vehicle revolution, presents the IPCC findings that transport activity is a key component of economic development and human welfare. Emissions from transport are rising faster than from any other energy sector around the world as economies grow as transport relies very heavily on fossil fuel for energy. Freight transport is a key component of transport emissions growth. Urban freight movements are predominantly by truck, while international freight is dominated by ocean shipping.


It projects that unless there is a major shift away from current patterns of energy use, world transport energy use is projected to increase at the rate of about 2% per year, with the highest rates of growth in the emerging economies, and total transport energy use and carbon emissions is projected to be about 80% higher than current levels by 2030 (medium agreement, medium evidence). These findings largely continue to apply today. The chapter notes ongoing debate about whether the world is nearing a peak in conventional oil production that will require a significant and rapid transition to alternative energy resources. Improving energy efficiency offers an excellent opportunity for transport GHG mitigation through 2030. It proposes that carbon emissions from 'new' light-duty road vehicles could be reduced by up to 50% by 2030 compared to currently produced models, assuming continued technological advances and strong policies to ensure that technologies are applied to increasing fuel economy rather than spent on increased horsepower and vehicle mass. Material substitution and advanced design could reduce the weight of light-duty vehicles by 20–30%.