In the Fifth Element, we see a great shot of future NYC which shows the statue of liberty and other recognizable elements sitting way up high on small mountains, with the sea line far below present day.

Is any reason given for this low sea level in the film or any other sources?

The quality of this image is excellent https://cdna.artstation.com/p/assets/images/images/000/787/268/large/wayne-haag-5th-fs11-1997-1200px.jpg?1433122122
– Bebop Jun 15 '20 at 03:11