The narrow streets of Bamberg, a charming old town in the German state of Bavaria, are hard to forget. I am particularly fond of the windows, many of which are decorated with window boxes of flowers displaying a profusion of colors.
　　And then I think of Jinan, the eastern Chinese city where I have lived for many years. The number of cars in Chinese cities has rocketed in recent years, with roads becoming ever more congested and the buildings alongside becoming taller. Instead of window boxes full of flowers, the only decoration on the outside of Chinese buildings tends to be air-conditioning units. As summer approaches, the news media carry reports of air-conditioning manufacturers’ sales promotions, with hundreds of new systems being sold in a single day, thousands in a single month. But there’s no mention of the ozone-depleting substances produced by some refrigerant gases, or how much power these appliances will consume and the associated emissions of carbon dioxide (CO2). In summertime business meetings, the air conditioning often is on at full blast, leaving attendees shivering. Sometimes a window is even left open to let some cold air out.
　　Summer in Bamberg can also be scorching, but no homes have air conditioning, and very few shops or buses do either. I used to wonder how they survived summer. A friend told me that even though the temperature can reach 42℃ (about 107° Fahrenheit), the locals have their ways of coping with the heat: take a walk by the river; sit under the trees; use an electric fan; have a cold drink—but do not install air conditioning. They know that air conditioning produces greenhouse gases and, to protect the environment, emission of those gases needs to be reduced. I was impressed. To protect the environment, the people of Bamberg are willing to make a sacrifice. But how many people are able to put this into practice?