600 million live in shanty towns while a further 100 million are believed to be homeless. 1 billion urban residents are exposed to health-threatening levels of air pollution. A tenfold reduction in resource consumption in the industrialised countries is a necessary long-term target if adequate resources are to be released for the needs of developing countries. Since World War 2, the number of vehicles on the road has risen from 40 million to 680 million. At current rates of expansion there will be 1 billion vehicles by 2025.
Transport is one of the major contributors to greenhouse gas emissions and urban pollution.
A survey of 200 scientists singled out water scarcity and climate change as the most serious environmental issues facing humanity in the 21st century. Next came deforestation and desertification. Average sea level is expected to rise by 50cm with devastating consequences. Climate change has been linked to the increasing ferocity of natural disasters. More than half the world's coral reefs are threatened by human activities.