The atmosphere is mainly heated by

The atmosphere is heated mainly by long-wave radiation given off by the Earth's surface.

Short-wave solar radiation largely passes through the air to warm the ground first.

Reflected solar radiation is bounced back to space and does little to heat the air directly.

Scattered solar radiation disperses light but is not the main heating mechanism.

The surface absorbs sunlight and re-emits it as long-wave heat that greenhouse gases capture.

This is why air temperature is generally highest a little after midday rather than at noon.