Hackers, cyber-warfare, and government censorship might be threats to the Internet in the present, but the biggest on-line problem in the future could be global warming.

The Internet relies on a vast physical network with large data centers linked together with thousands of kilometers of fiber optic cable buried underground.  The cable was designed to be moisture-resistant, but flooding is something else.  And global warming is making the seas rise faster than predicted.

A new study (.pdf link) from researchers at the University of Wisconsin-Madison and the University of Oregon says the physical Internet was not built to withstand being submerged.  "When it was built 20-25 years ago, no thought was given to climate change," said computer science professor Paul Barford of University of Wisconsin-Madison.  

The researchers took maps produced by the US National Oceanic and Atmospheric Administration (NOAA) that predict where rising seas will cause urban flooding, and overlaid them onto corresponding maps locating the Internet's physical infrastructure.  And it's not good.

Professor Barford said the consequences of this bad planning could start to show up by 2033.  He told this week's joint meeting of the Association for Computing Machinery, the Internet Society, and the Institute of Electrical and Electronics Engineers that within 15 years, as many as 6,500 kilometers of buried fiber optic conduit could be submerged and 1,100 traffic hubs could be underwater.

"Most of the damage that's going to be done in the next 100 years will be done sooner than later," warned Barford.  "That surprised us. The expectation was that we'd have 50 years to plan for it.  We don't have 50 years."