A proposed U.S. system to protect satellites from solar storms or high-altitude nuclear detonations could cause worldwide radio communications blackouts, according to a group of scientists from New Zealand, Finland and the United Kingdom.

The planned radiation belt remediation system, being developed by the U.S. Air Force and the U.S. Defense Advanced Research Projects Agency, involves using very low frequency radio waves to flush particles from the radiation belts and dump them into the upper atmosphere.

The plan would protect low-earth orbiting satellites from having their onboard electronics ruined by charged particles but would alter the upper atmosphere in the short term, disrupting high frequency radio wave transmissions and GPS navigation around the globe.

“We’ve calculated that Earth’s upper atmosphere would be dramatically affected by such a system, causing unusually intense HF blackouts around most of the world,” Craig Rodger, lead researcher and senior lecturer in the Department of Physics at University of Otago, said in a statement.

The deluge of dumped particles would temporarily changing the ionosphere from a “mirror” that bounces high frequency radio waves around the planet to a “sponge” that soaks them up, Rodger said. “Airplane pilots and ships would lose radio contact and some Pacific Island nations could be isolated for as long as six to seven days, depending on the system’s design and how it was operated.” GPS would likely also suffer large-scale disruptions, as signals between ground users and satellites were scrambled by the ionosphere, he said.