Brazil's President Dilma Rousseff (R) listens to UN Secretary General Ban Ki-Moon at the Rio+20 Wednesday
Brazil's President Dilma Rousseff (R) listens to UN Secretary General Ban Ki-Moon at the UN Conference on Sustainable Development Rio+20 opening ceremony in Rio de Janeiro, Brazil, on June 20. World leaders kicked off a three-day summit on environment and poverty in Rio on Wednesday to a warning from Ban Ki-moon that "time is not on our side" for fixing a mounting list of problems.