Carbon dioxide isn't the only gas responsible for the greenhouse effect, but it does account for around half of global warming. Methane is the other major contributor, but it's a lot harder to limit the output of this gas, so sights are set securely on CO2.
By burning fossil fuels, the transport sector is responsible for around 25% of CO2 emissions, with aviation and cars the main culprits.
The European Union has now set targets for a reduction in the CO2 emitted by cars, with their aim being an average of 120g/km by 2015 - 25% less than the figure in 2008. The target will be phased in over three years, starting off with 65% of cars needing to meet the target in 2012, with that figure climbing to 75% and 80% in 2013 and 2014 respectively.
Although there are concessions for manufacturers who make low numbers of cars – their target is to cut emissions by 25% from their 2007 levels – makers who fail to meet these targets will face fines. Experts also agree that car makers have to look at alternative energy sources and that the transport industry and car makers have to take the issue much more seriously.
If we don't curb CO2 output from cars, the planet will continue to warm up. The main consequence will be an increase in the instability of our weather systems, so instead of having a catastrophic flood in the UK once every century, we might have one every 10 years.
The Intergovernmental Panel on Climate Control (IPCC) reckons average temperatures could rise by as much as six degrees by 2100 if we carry on the way we are.
The proportion of the world’s land surface that’s able to support human habitation would shrink – perhaps by 15-20% by the end of the century. There will be a serious loss of quality of life and mass forced migration. Places will become massively overpopulated – and it’s going to affect your kids’ generation.
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