Future Megacities.docVIP

Future Megacities 　　 　　The data shows that at present over 50% of the population in the world have already lived in cities， and by 2030， nearly 60% of the population in the world， namely about 5 billion， will inhabit in cities. Sustainable urbanization is therefore becoming the more urgent challenge faced by the global society in 21st century. As the first international day in relation to cities， and also the first international day initiated by Chinese government， the designation of World Cities Day will focus on the development issues of city and pay attention to the efficiency improvement and technology innovation in the process of global urbanization， aiming to carry out effective management in cities with population agglomeration， reduce resources and energy consumption， and achieve an orderly and healthy growth of cities. 　　The predicted population of 10 billion by 2100 （some even predict 11 billion） and the rapid growth of megacities will throw up many challenges. These growing cities will need major infrastructure to cope and it is easy to wonder whether future cities will be places of chaos and inequality， with shortages of essential services， energy and food. 　　The challenges are great. Tackling CO2 emissions is probably the most urgent and difficult challenge in the Anthopocean era， as we are currently producing more CO2 than the Earth’s ability to absorb it. As almost all city activity is responsible for greenhouse gas emissions （the UN estimates cities to be responsible for 70% of global CO2 emissions） society will have to find new low carbon solutions. There are many fanciful ideas about engineering our 7way out of the climate change predicament， such as fertilising the oceans to encourage phytoplankton to absorb CO2 or peppering the stratosphere with trillions of reflective discs to deflect the sun’s rays， but the more reasonable approach will be to find carbon neutral solutions for our cities and to modify our behaviour somewhat. 　　The rat