A combination photo shows a view of Yintai Centre (L) and China World Trade Centre Tower III (R) before (top) and during Earth Hour in Beijing's central business district, March 23, 2013. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 pm local time, is meant as a show of support for tougher action to confront climate change. [Photo/Agencies]