Popular culture often portrays tropical rainforests as sweltering, but they cool themselves naturally. So what better place to discuss how cities in different climates can tackle extreme urban heat than Xishuangbanna, China's only tropical rainforest city.

CGTN's Yang Xinmeng joined mayors from around the world there. The consensus: there is no one-size-fits-all solution but rainforests offer a lesson. They do not fight heat, they stop it from building up in the first place.

Protecting forests, hills and rivers should be a priority for all. The first step is to wean the world off coal, oil and gas, and develop green economies instead. Nature knows how to build cool, livable places.