Climate weeks have become the connective tissue of the climate calendar: open, citywide gatherings where the real dealmaking happens between COPs. But if you work in development, health, or philanthropy, they're one piece of a bigger calendar — so we put them in context: every climate week we rate, in date order, alongside UNGA week, the COPs, and the rest of the impact calendar, with dates confirmed as they're announced.
Decentralized, open-calendar weeks organized by and for a city's climate community: Climate Week NYC (the biggest, alongside UNGA), Bangkok Climate Action Week (Asia Pacific's largest), London Climate Action Week (green finance), SF Climate Week (climate tech and capital), and São Paulo Climate Week (the LatAm anchor). Mostly free, no badge required, hundreds of independent events each.
Since 2025, UN Climate Change runs two official Climate Weeks a year in different regions, combining mandated intergovernmental meetings with implementation dialogues on the road to the next COP. In 2026: Yeosu, Republic of Korea (April) and Baku, Azerbaijan (October). These are working sessions, not festivals.
Everything above orbits the annual UN climate conference. COP31 lands in Antalya, Turkey, November 9–20, 2026, and the city weeks are increasingly where its action agendas get built and carried forward.