How Rain Launches Microplastics into the Air express

Original: "Droplet Impact on Microparticle Raft: Wettability, density and size govern splashing and microplastic ejection from rafts under raindrop impact"
arXiv:2603.15896 · 2026-03-16 · CC BY 4.0 · 1 min
Raindrops knock plastic debris off the water's surface and send it into the air we breathe.

The Sun drives the water cycle, and rain returns it to the ground. But now, every drop is a tiny hammer striking the surface. Floating plastic particles (microplastics, mostly carbon) upon impact jump up like popcorn kernels on a hot skillet. But instead of popping, they get wrapped in a thin water film and turn into weightless beads. Wind catches them and carries them thousands of kilometers — from city puddles to mountain glaciers. The particles that fiercely repel water jump the highest: they bounce up several centimeters and can drift in the air.

Researchers have found a simple rule: how much plastic enters the atmosphere depends on the force of the drop's impact and the 'water-hating' nature of the particles. This helps predict what we breathe after a downpour. The same mechanism works when drops hit sand: this is how rain erodes shores and transports soil.

Plastic particles that fiercely repel water can jump up several centimeters and float in the air like miniature balloons.

Scientists
Enrico FermiDaniel BernoulliLeonhard EulerArchimedesFred Lawrence WhippleJohn Henry Poynting
Concepts
rainfall microplastic dispersion precipitation drag wind stress impact impact force microorganism swimming dynamics fluid flow lubricant microswimmer molecular interaction porosity microparticle surface tension protoplanetary disk winds ocean current droplet Starling's law hydrodynamics obstacle