The biggest environmental problem: too many people

observer.guardian.co.uk — If governments want to cut greenhouse gas emissions we have to address the accelerating growth in the world's population, expected to increase from 6.7 billion now to 9.2 billion by 2050. Some population activists argue the world can only support a population of two to three billion, even as few as 500 million in future. Mar 18, 2007 View in Crawl 4