the ground radiates solar energy into air & solar energy can warm up the air ->  the solar energy radiated by the ground can warm up air  if gas is heated then that gas will rise & air is a kind of gas ->  if air is heated then air will rise  the solar energy radiated by the ground can warm up air & if air is heated then air will rise ->  the solar energy radiated by the ground can cause the air to rise  the solar energy radiated by the ground can cause the air to rise & travelling up a mountain side is a kind of rising -> the solar energy radiated by the ground can cause the air to travel up a mountain side