At least 20 % of government transport budgets should be invested in infrastructure for walking and cycling , according to the United Nations Environment Programme ( UNEP ) . Such infrastructure would reduce pollution and emissions whilst also saving lives . A quarter of all global carbon emissions are caused by motorised transport , which is the quickest - growing transport sector . This type of transport is expected to cause a third of all emissions by 2050 , with the number of private cars tripling by 2050 . UNEP argues that the growth , primarily in developing countries , will damage the world ’s ability to achieve the terms of the Paris Climate Agreement .
At least 20% of government transport budgets should be invested in infrastructure supporting walking and cycling, according to the United Nations Environment Programme (UNEP). Such investment would reduce pollution and emissions whilst also saving lives. A quarter of all global CO2 emissions are caused by motorised transport, which is the quickest-growing emissions sector. This type of transport is expected to cause a third of all emissions by 2050, with the number of private cars tripling by 2050. UNEP argues that the growth, primarily in developing countries, will damage the world’s ability to achieve the terms of the Paris Climate Agreement.