Shinjiro Koizumi

On Nov. 20, in the midst of his third (and potentially final) term, Prime Minister Shinzo Abe will become Japan’s longest-serving Prime Minister. Many voters already know whom they would tap to succeed him: 38-year-old Shinjiro Koizumi. In his first weeks as the Environment Minister in Abe’s Cabinet, Koizumi raised eyebrows by saying he wanted to make the fight against climate change “sexy” and “fun.” But he also had an early success to tout: Yokohama, Japan’s second most populous city, joined Tokyo and Kyoto in pledging to reduce carbon-dioxide emissions to net zero by 2050. —Charlie Campbell