Convection currents are part of what drives global circulation of the Earth's atmosphere. The sun heats the air near the earth’s equator, which becomes less dense and rises upward. The minimal convection in zero-g causes many flames to smother themselves in their own combustion … In the atmosphere, as air warms it rises, allowing cooler air to flow in underneath. As it rises, it cools and becomes less dense than the air around it, spreading out and descending toward the equator again. As it rises, it cools and becomes less dense than the air around it, spreading out and descending toward the equator again. Convection drives the circulation of air in the earth’s atmosphere.

! The exception is that combustion in a zero-gravity environment lacks buoyancy, so hot gases don't naturally rise, allowing fresh oxygen to feed the flame. Lighter (less dense), warm material rises while heavier (more dense) cool material sinks. The sun heats the air near the earth’s equator, which becomes less dense and rises upward. What does a convection current do? Convection drives the circulation of air in the earth’s atmosphere. It is this movement that creates circulation patterns known as convection currents in the atmosphere, in water, and in the mantle of Earth. Hope this helps! Combustion generates convection currents.