BBC: The ionosphere is the first atmospheric layer that GPS radio signals encounter on their way from space-based satellites to Earth. When solar activity causes the layer to fluctuate, GPS signals can be significantly impacted. To quantify the effect, University Centre in Svalbard, Norway, is running a monitoring project. On a normal day, GPS readings in Svalbard, which is halfway between the Norwegian mainland and the North Pole, can be off by 1–3 m; strong solar storms can result in errors of several tens of meters. By firing a 16-MW radio signal into the ionosphere, researchers are attempting to duplicate the disruption caused by solar flares. Just as the visible effects of solar flares—the auroras—are most noticeable in polar regions, GPS disruptions there are also more significant. And because of melting polar ice, industries that are heavily reliant on accurate GPS navigation, such as oil drilling and shipping, are expanding into arctic regions. Understanding the effects of solar storms on GPS signals will help increase safety for polar industry.