“Maybe the island is sinking”
.
Sinking of Pacific islands is helped by building airport runways on them.
(As the CCP has learned recently, just as the Japanese learned before WWII).
AND Japan’s “Kansai International Airport”, which has another 13 feet yet to sink. (!)
On the right notice the larger islands. On the left the island get progressively smaller. This is because these island are on a geological conveyor belt. Volcanic activity forms the islands on the rights. Over time these islands drift west on the sea floor and wear down and subside.