When the air particles bunch up, it's called a

When the air particles bunch up, it's called compression.
Hope this helps, as compress means bunch up and force particles together so it must be compression from most of my science knowledge.
:)

The horse latitudes-high-pressure zones about 30 degrees north and 30 degrees south of the equator.-warm air traveling away from the equator cools and sinks-weather tends to be clear and drythe doldrums-low-pressure near equator-air rises and spreads out toward the poles-rising moist air produces clouds and heavy rainthe westerlies-blow from the west-move from the horse latitudes toward the poles.-bring storms across much of the united statesthe tradewinds-blow from the east-move from the horse latitudes toward the equator  -strong, steady winds

Some type of thing that was invisible