Nanoparticle Bursts over the Amazon Rainforest

Atmospheric aerosol particles are essential for the formation of clouds and precipitation, thereby influencing the Earth’s energy budget, water cycle, and climate. However, the origin of aerosol particles in pristine air over the Amazon rainforest during the wet season is poorly understood. A new study reveals that rainfall regularly induces bursts of newly formed nanoparticles in the air above the forest canopy.

Growing cloud seeds in the Amazon rainforest

In a new study, Marco A. Franco and his colleagues analyzed when and under what conditions aerosols grow to a size relevant for cloud formation. Such growth events are relatively rare in the Amazon rainforest and follow and pronounced diurnal and seasonal cycles. The majority take place during the daytime, and during the wet season. But the team also discovered a few remarkable exceptions.