The water levels around the world are rising, and global warming isn’t the only cause. Along with the rest of the tides cycle, the most dramatic cycles is the 100,000 year cycle of the ice age. During this time, the poles expand to cover much of Europe, Russia, and South Africa in mile thick ice. The amount of water trapped in the ice is enough to drop the sea level by 40 feet, exposing the continental shelves. Like every dramatic action, it has an opposite reaction.
The last major ice age was around 30,000 years ago. That puts us in the cycle of warming and melting of the icecaps. The oceans are rising and taking back the land they once gave us. On top of the natural warming, the effect of the green house gasses we produce is amplifying an hastening this natural cycle.
The rising water level are a huge problem form many small island nations. Some nations are loosing their island already. Others, like Maldivians, are planning to buy land to still have a country. The rising water levels could wipe out entire cultures.
Not even the bigger land masses are free of danger. London, Venice, and the Netherlands already faced a major flood event caused by a combination apogee tide and severe storm system. They were force to build new tide wall systems to sustain the next fifty years, but what then?