How much land are we going to lose due to sea levels rising by 2050?

On average, the global sea level is expected to rise by about 40 cm, nearly half a meter, by 2050. Of course, sea level rise depends on how much carbon dioxide emissions are released by humans. However, in 2050 there actually isn’t much difference between predictions of the best (RCP2.6) and worst (RCP8.5) case scenarios. It is not until after 2050 that their paths really diverge. That’s because it takes a lot longer for the ocean and ice on the planet to respond than the atmosphere.  

Interestingly, the amount sea level rise will be quite different depending on where you are.  In Sydney, for example we might expect .2 m by 2050, but in NYC it could be up to .45. This is because there is a lot more land in the northern hemisphere and all that land is very heavy. Its weight actually pulls water to the north via the force of gravity. 

To calculate how much land that increase in sea level will flood, you also need to consider how far above sea level the coast line is. Over all, once you consider the shape the coastline around the world, we could be looking at 4.3 million acres underwater. That land contains the homes of 40-150 million people.