The mainland's top weather official has issued a stark warning on climate change, saying that rising temperatures could have "huge impacts" on the world's most populous country, state media reported on Sunday. Global climate change would reduce crop yields, lead to "ecological degradation" and create unstable river flows, Xinhua quoted Zheng Guoguang , chief of China's Meteorological Administration, as saying. "As the world warms, risks of climate change and climate disasters to China could become more grave," Zheng said. China is the world's largest source of carbon dioxide emissions which cause climate change. Beijing has said it aims for those emissions to peak "around 2030". Temperature increases on the mainland over the past century had been more extreme than global averages, Zheng added. He described climate change as a "serious threat" to several mega-projects including the vast Three Gorges Dam, a railway connecting Tibet with northwest China, and a huge scheme to divert water from the country's south to its dry north. Zheng called for China to take a "low-carbon development path". But Xinhua also quoted him as saying the potential for wind and solar energy was "limited", without giving details. China and the United States, which together produce around 45 per cent of the world's carbon dioxide, will be key to ensuring a global deal on reducing emissions after 2020 at a Paris summit later this year. The Communist Party has for decades emphasised economic growth, which has caused demand for energy - especially coal - to skyrocket. Coal use grew by an average of 9 per cent each year from 2000 to 2010, according to the US Energy Information Administration. Beijing has pushed for alternative schemes - such as facilities that convert coal into gas - but these have been criticised as resulting in greater emissions.