The future of the world’s climate will be decided in the cities and by the way in which human beings feed themselves. Never before have so many people lived in urban centres, such as those in Asia, Africa and South America. But megacities in their present form are huge consumers of resources. Governments that want…

(151221) -- TEHRAN, Dec. 21, 2015 () -- Photo taken on Dec. 20, 2015 shows a view of smog-enveloped Tehran, Iran. Iran's government announced that all schools and kindergartens of Tehran close on Dec. 20 and 21, due to the alarming high air pollution in the city. (Xinhua/Ahmad Halabisaz) |