Climate change is given plenty of coverage here, and by now you’re all more than well aware of what we stand to lose. But, as these things so often are… it’s going to be worse than you think. In a new way this time, though!

Rising sea levels could critically damage and disrupt the core backbone of the internet. While many understand the internet is literally a giant network, most generally think that the traffic gets passed through satellites. Not so, actually. There are thousands of miles giant undersea cables that run across the world, making up the primary data linkages between the continents.

This week, a new study presented at a conference on internet research and infrastructure concluded in just 15 years more than 4,000 miles of coastal cables.

“The results in the paper are startling,” lead author of the paper Paul Barford, told Earther. “There’s gonna be a great deal of infrastructure that’s gonna be underwater in the next 15 years.”

The paper is fairly direct and looks at maps of the physical internet infrastructure and compares that to sea level rise projections from the National Oceanic and Atmospheric Administration.

To get a preview of how bad this can be, we need only look at the flooding caused by Hurricane Sandy. It flooded large chunks of New York’s cable systems, and that corresponded to an uptick in outages across the United States for the next few days. Prolonged waterlogging and inundation, though, would be much worse. And, we’re only talking about the relatively meager rise expected in the next decade and a half. Still, that could severely impact those in coastal cities… like, y’know. Most of the major ones. And due to the connected nature of the web, that will likely lead to similar problems for people all over the US.

“Hopefully, our findings will alert people that we don’t have 100 years to solve this,” Barford said. “We need to start looking at it very soon so that we can take steps to ensure our communication capability in the United States.”