For the first time ever, researchers used the power of big data to calculate country-by-country greenhouse gas emissions from air transport for the 197 countries covered by the international climate change treaty. When countries signed the United Nations Framework Convention on Climate Change in 1992, high-income countries were required to report their aviation-related emissions. But 151 middle- and lower-income countries, including China and India, were not required to report these emissions, although they could do so voluntarily. (Nancy Bazilchuk, Norwegian University of Science and Technology, more at phys.org)