If you were around the in the mid-90’s, there was an epic Hollywood blockbuster film, “Waterworld”, starring Kevin Costner. The premise was the world’s polar ice caps melted and the planet was almost completely inundated leading to a dystopian apocalypse. In midst of scarce resources, one of which being fresh water, you see Kevin Costner’s character purifying and drinking his own urine. Ok, we’re getting a bit off topic here but you get the idea about global sea levels rising and it’s happening for real, with or without recycled urine.

Sea levels are rising at an increasing rate of approximately 3 cm per decade (or about 1/8 inch per year) since 1992 – significantly higher than any other time over the last 2000 years. Not only is it rising, it is rising at an increasing rate. This is caused by thermal expansion of water and melting glaciers and polar ice caps which is a direct result of global warming. The concept is pretty simple: as sea levels continuously rise, it will start to flood and inundate more land beginning with small islands and coasts, including coastal cities. The opening scene of Waterworld gives a pretty good (entertainment-realistic) animation of how this happens and huge credit to Hollywood for contributing to this kind of discussion. There is eventual widespread flooding on a global scale that makes once habitable land, uninhabitable. If you consider the plethora of coastal cities we currently have in the world with a lot of them being major economic hubs, that’s a gargantuan amount of damage. The world’s coastal cities are going to go under if nothing is done about it.

Higher sea levels also mean more destructive storm surges that push further inland than they did before. Hurricanes and typhoons move more slowly and drop more rain which coincides with their increased force. Subsequent effects of erosion, agriculture soil contamination with salt and flooding compound the devastating impacts. It’s important to remember that while it was a happy ending for Kevin Costner in Waterworld, the world was already pretty screwed at the start of the movie.