Brazilian President Dilma Rousseff speaks during a joint news conference with US President Barack Obama in the East Room of the White House, in Washington DC, last week. Obama and Rousseff committed to “intensify collaboration . . . to address the challenges posed by climate change”. The two Presidents also called for a successful outcome to the so-called ‘COP 21’ climate negotiations, which are scheduled to take place in Paris, France, from November 30 to December 11.