Indonesia's Cities Rank Among World's Highest in Extreme Humid Heat, Raising Health Risks

A Climate Central report titled *Global Analysis: Dangerous Humid Heat Rising Due to Climate Change* found that ten Indonesian cities are in the world’s top‑50 for the number of extreme humid‑heat days recorded between 2016 and 2025. Pekanbaru leads with 353 days, followed by Medan (342) and Surabaya (313), all placed within the global top‑10. Jakarta, Tangerang Selatan and Tangerang also record very high totals, with 210 of Jakarta’s 290 extreme‑heat days (about 72%) attributed directly to climate change.

The study shows a rise from an average of 82 extreme humid‑heat days per decade in the 1970s to 174 days in the 2016‑2025 period, with roughly two‑thirds of the increase driven by the climate crisis. Scientists warn that wet‑bulb temperatures of 25 °C or higher impair the body’s ability to cool, heightening risks of dehydration, heat‑stroke, cardiovascular and respiratory problems. Indonesian health and climate advocates, including Bondan Andriyanu of CERAH and pediatric specialist Lisa Patel, stress the need for emission reductions and targeted public‑health measures to protect vulnerable urban populations.