Carbon emissions will result in global warming which will result in rising sea levels which will swallow up some of the largest cities on the planet, a new study is warning.

London, New York, Tokyo, and Hong Kong will sleep with the fishes if the world burns all of the fossil fuel reserves that are currently available, a new study says as reported by The Independent.

The resulting carbon emissions from burning through coal, oil, and gas reserves would ramp up global warming to the point that almost all of the Antarctic ice sheet would melt and spill into the sea, causing sea levels to increase by 60 meters, which would flood areas that are currently populated by a billion people.

Scientists have so far focused on melting on the western part of the Antarctic ice sheet, but this study examines the consequences of the entire ice sheet melting should fossil fuel burning continue. The west is more advanced in melting than the east, but the eastern sheet could very well melt as well and it would contribute severely to the rise in sea levels.

Humanity may be able to handle losing the West Antarctic Ice Sheet, and in fact it may be too late, but if the east sheet is lost as well, it will jeopardize these major cities around the world, the researchers warned.

So what’s the solution? Scientists say there’s only one: stop burning through fossil fuels and dumping CO2 in the atmosphere, or there may be a billion people under water one day.

Although scientists don’t think it’s terribly likely that the world will manage to burn through all of the fossil fuel reserves, but there’s certainly the possibility that a large portion would be consumed, which in itself could cause problems for the ice sheet. If emissions continue to increase each year, this would happen within 150 years.