Above adjective – Appearing earlier in the same text. Upper and above are semantically related in place topic. In some cases you can use "Upper" instead an adjective "Above".
Upper adjective – Higher in place or position. Above and upper are semantically related in position topic. You can use "Above" instead an adjective "Upper", if it concerns topics such as place.
A phoenix above the main entrance of Hamburg's city hall symbolizes the rebirth of the city after the great fire of 1842, as does the representative Phönixsaal (Phoenix Hall) on the upper floor.