Reuters: Curbing climate change would cost no more than 1 percent of global income per year, and the world can afford it, development economist Jeffrey Sachs said on Wednesday. “If we look seriously at mitigation, it is not too expensive,” he told a conference in Geneva on the humanitarian impact of climate change. “If we invested around $700 billion per year, we would be able to create a sustainable energy system.” The United States spent just $3 billion …