Canadians in China population of 200,000 are from Canada (20,000). The Canadian diaspora in Beijing is a young and well-educated community and is economically active. A significant number of them include Chinese Canadian returnees who emigrated to Canada in the early 1990s and later returned to China. According to local official statistics, the numbers of Canadian citizens residing in Shanghai have increased significantly over the past ten years. In 2000, the city reported 1,361 Canadian citizens living there, representing 2.3% of all foreign residents in the city. By the end of 2009, there are about 6,121 Canadian citizens living in Shanghai. Shanghai's Canadian
Environmental issues in China cumulative largest. China has ratified the Kyoto Protocol, but as a non-Annex I country is not required to limit greenhouse gas emissions under terms of the agreement. Various forms of pollution have increased as China have industrialized which has caused widespread environmental and health problems. China has responded with increasing environmental regulations and a build-up of pollutant treatment infrastructure which have caused improvements on some variables. As of 2013 Beijing, which lies in a topographic bowl, has significant industry, and heats with coal, is subject to air inversions resulting in extremely high levels of pollution in winter months. In response