According to my current observation of Japan, all the islands in Japan should sink to about 3000 meters below sea level in 20 15 years. People on the island can't get out of trouble because of natural disasters, most of them will be submerged by seawater, some of Jamlom will be swallowed up by fish and sea monsters, and those who survive in the end will mutate due to environmental impact and eventually become amphibians such as fish.