Cities in Asia and the United States emit the most heat-trapping gas that feeds climate change, with Shanghai the most polluting, according to new data that combines observations and artificial intelligence. Seven states or provinces spew more than 1 billion metric tons of greenhouse gases, all of them in China, except Texas, which ranks sixth, according to new data from an organisation co-founded by former US Vice President Al Gore and released Friday at the United Nations climate talks in Baku, Azerbaijan. Nations at the talks are trying to set new targets to cut such emissions, and figure out how much rich nations will pay to help the world with that task. Using satellite and ground observations, supplemented by artificial intelligence to fill in gaps, Climate Trace sought to quantify heat-trapping carbon dioxide, methane and nitrous oxide, as well as other traditional air pollutants worldwide, including for the first time in more than 9,000 urban areas. Earth's total carbon ...