Climate researchers say it will require removing billions of tons of carbon dioxide from the atmosphere to return to a climate that isn’t threatening us with dangerous levels of global warming. But that will necessitate finding a way to make such a massive climate control effort economically feasible. Fulton Schools Professor Klaus Lackner, a carbon capture pioneer and director of ASU’s Center for Negative Carbon Emissions, and Habib Azarabadi, a doctoral student and researcher at the center, recently authored a research paper that estimated what would be needed to make eliminating great amounts of carbon dioxide economically viable. They estimate it would take technology that can remove the greenhouse gas at a cost of about $100 per ton — far less than what current technologies can achieve. Experts say overcoming that drawback can be achieved only by governments, major industries and research institutions collectively committing to finding solutions.