Urbanization in China or 37 percent of the total population in the mid-1980s—was relatively low by comparison with developed nations, the number of people living in urban areas in China was greater than the total population of any country in the world except India. The four Chinese cities with the largest populations in 1985 were Shanghai, with 7 million; Beijing, with 5.9 million; Tianjin, with 5.4 million; and Shenyang, with 4.2 million. The disproportionate distribution of population in large cities occurred as a result of the government's emphasis after 1949 on the development of large cities over smaller urban areas. In 1985 the
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