Answer:
Invisible convection currents are revealed using a very colorful demonstration.
Cool, crisp, clean mountain air has long been an important reason why people move to Colorado, USA. Unfortunately, the air in the city of Denver isn’t quite as clean as it has been. By the 1970s, pollution over the city had a name—the “brown cloud.” Denver’s location at the foot of the Rocky Mountains makes it prone to temperature inversions in which warm air higher in the atmosphere traps cooler air near the ground. This condition prevents pollutants from escaping into the atmosphere. However, the phenomenon of temperature inversion is not unique to Denver, as evidenced by numerous reports of similar brown cloud sightings over major cities throughout the world. This demonstration provides a great illustration of what’s really happening in the atmosphere as hot and cold air masses meet.
