From internet shopping to long-haul holidays, our busy lifestyles mean people and goods are on the move like never before. But all that movement comes at a cost above and beyond the delivery charge or ticket price.
Transport emissions – road, rail, air and maritime – accounted for more than 24% of global CO2 emissions in 2016, the World Resources Institute (WRI) reported last year. And they are expected to grow at a faster rate than any other sector – posing a major challenge to efforts to reduce emissions in line with the Paris Agreement and other global goals.
Improvements in vehicle efficiency are being more than offset by a greater overall volume of travel. In the US, for example, after a decline in transport-related emissions from their peak in 2005, emissions plateaued and have now risen every year since 2012, according to the WRI. In 2016, the transport sector surpassed the electric power industry as the single greatest emitter of greenhouse gases for the first time.
In terms of transport modes, 72% of global transport emissions come from road vehicles, which accounted for 80% of the rise in emissions from 1970-2010. Emissions have also increased in the aviation and maritime sectors – with the rail industry, largely powered by electricity, the only one where emissions have declined.
In terms of geography, transport emissions mostly come from upper-middle-income and high-income countries – with South Asia and Sub-Saharan Africa contributing less than other regions. The 10 countries with the largest transportation emissions in 2014 were the US, China, Russia, India, Brazil, Japan, Canada, Germany, Mexico and Iran – together, these countries contributed 53% of global transport emissions.
To keep global temperature rises within a range that averts the worst climate impacts, International Energy Agency modelling suggests that transportation emissions need to peak around 2020 – so there's no time to waste. Clean fuels and vehicle efficiency have a huge part to play – but on their own they're unlikely to go far enough. It's time for a fresh look at how we build and run cities – and how we move people and goods.
In the UK, for example, Birmingham has recently announced plans that could see cars banned from driving through the centre of the city. Motorists wanting to get to the centre would find it divided into 'cells' – and would only be able to enter them from particular parts of the ring road. They would have to go back out to the ring road to access other parts of the city centre – in the hope that banning 'through trips' would cut pollution in the city centre.
But this doesn’t really solve the problem – it's more a case of moving it elsewhere. Tackling the issue on a national or global scale needs a data-driven, joined-up approach covering everything from public transport networks to road haulage route optimisation.
If cities embrace automation, electrification and ride sharing, for example, research suggests they could cut transport emissions by 80%. So just think what we could achieve if we harness big data to optimise the entire planet…