It is believed that global flooding can begin quite suddenly. Archeology has shown that the last Ice Age went from balmy weather to ice within 20 years. As the permafrost and the glaciers melt the melting increases steadily. The same thing happens in your freezer. You can unplug it and open the door and the ice will sit there for awhile and it won't look like anything's going on. Then it begins to melt. And it keeps melting faster and faster because there is less coldness nearby to keep the remaining ice cold. The other factor is the reflectivity of the ice itself in beaming the sun's rays back up. With less ice there is less white surface to reflect back.

Bernal will be safe since it is built largely on rock. Most of SF will not be safe as it is built largely on sand.

The country of Tuvalu is quickly losing its land mass, and it has been increasing each year. Soon there will be no Tuvalu left. They can no longer farm in some areas and their economy has taken a hit. The only saving grace is that the Internet domain name suffix for Tuvalu is .TV, which is being sold to lots of people who want a .TV on their domain names. This is oddly enough helping to keep their economy going. The people of Tuvalu have petitioned various countries to accept them as citizens. I'm not sure if any country has taken them in or not. Imagine being without a country because it disappeared beneath the ocean.