From June through October, it's not unusual for huge Saharan dust plumes to blow across the Atlantic. They can darken skies but also bring calmer weather and electric sunsets. Here's how they form.

In South Asia, days with both extreme heat and extreme pollution are expected to increase 175% by 2050. Separately, the health effects are bad; together they will likely be worse.

Just a handful of facilities that emit unusually high levels of toxic chemicals account for the majority of industrial pollution year after year.

Yes, poor air quality is bad for your health – but beware simplistic correlations with COVID-19.

"The optical tweezers allow us to ... directly probe the dynamic evolution of all these critical properties of atmospheric particles and how they feedback on each other as each particle continues to evolve."

Auto emissions are key to the creation of "ultrafine particles," which have been linked to health problems and birth defects, researchers say.

3D printers produce particles that can negatively affect air quality indoors, make the air toxic, and potentially harm respiratory health.

"Some people call this higher concentration of pollutants around the human body the personal cloud... we call it the 'Pig-Pen Effect.'"

The developers of a nonthermal plasma method for killing airborne viruses hope it can one day replace the surgical mask.

"We're basically saying: 'Hold on, don't worry. Things might look like they're getting worse, in some places, but overall they should get better.'"