Forests are nature’s air conditioners: new research reveals how trees keep communities cool and climate-resilient

While forests have long been championed as carbon storage powerhouses in the fight against climate change, groundbreaking new research reveals they’re doing much more than just absorbing CO2. A comprehensive scientific review demonstrates that forests act as natural climate regulators, providing immediate cooling benefits that help communities adapt to our warming world today.

The study, which analyzed nearly 100 field sites globally, found that forests function like massive air conditioning systems. Tree canopies create shade while driving evapotranspiration—a process that converts heat into water vapor. This natural cooling mechanism makes daytime temperatures inside forests an average of 4°C (7°F) cooler than nearby open areas, while nighttime temperatures remain slightly warmer, effectively smoothing out dangerous temperature extremes.

The cooling effect becomes even more dramatic in hotter climates. Tropical forests can be more than 6°C (11°F) cooler than cleared land, while even urban trees provide measurable relief, dropping air temperatures by roughly 1.5–1.7°C on sunny days. During heat waves, the difference becomes life-saving: apparent temperatures inside forests have been recorded as 6–14.5°C (11–26°F) lower than in open areas—a gap that can mean the difference between comfort and heat stroke.

This research underscores that protecting existing forests isn’t just about future climate goals—it’s about immediate human survival and well-being. As extreme heat events become more frequent and deadly, forests represent a critical natural infrastructure for helping communities adapt to our changing climate while we work to address its root causes.