Reuters: A 160-nation U.N. climate conference in Ghana split on Friday over ways to pay poor countries to slow deforestation, blamed for producing up to 20 percent of the greenhouse gases caused by human activities. Options suggested for raising billions of dollars in incentives include markets that would allow trading in the carbon dioxide locked up in trees, higher aid from rich nations and levies on airline tickets or on international shipping. "It’s important that we get to grips …