Which city is better in Guangzhou, Shanghai, Shantou and Tianjin?

Each has its own advantages. Shantou is closest to Xiamen. If you are afraid of cold, you'd better choose Guangdong. The weather in Guangdong is like spring all year round, especially in Guangzhou, because there are many factories, people and cars here, just like it snowed and froze last year, but the lowest temperature in Guangzhou is not lower than 3℃, and so is Shantou.