Aurora Storms Scramble GPS Signals

Scientists have discovered that intense, fast-moving auroras during a space storm called a ‘substorm’ can severely disrupt GPS signals, creating highly localized zones where navigation could fail.

On November 3, 2013, researchers in Svalbard, Norway, witnessed a spectacular auroral substorm. But they weren’t just watching the sky; they were also listening to signals from navigation satellites. Using highly sensitive GNSS receivers, they noticed something startling. As the aurora erupted and expanded rapidly across the sky, the signals from GPS, GLONASS, and Galileo satellites passing through the brightest, leading edge of the aurora became severely scrambled. It wasn’t the entire auroral display causing the problem, but a very specific, intense, and fast-moving part of the storm. The disruption was so localized that a receiver in Longyearbyen recorded severe interference on half its tracked satellites, while another receiver in Ny-Ålesund, just 120 km away, saw almost nothing. This was concrete proof that the aurora’s most violent moments can create invisible storms for our technology.

Original Research Paper: ‘Severe and localized GNSS scintillation…’ (J. Geophys. Res.)

The area of scintillation followed the intense poleward edge of the auroral oval.
— Christer van der Meeren, Lead Author

Imagine looking at a coin at the bottom of a perfectly still swimming pool. The image is clear. Now, imagine the water has ripples and waves. The coin’s image becomes distorted and blurry. GNSS scintillation is the same idea, but for radio waves. Satellites send signals through the ionosphere, a layer of our upper atmosphere filled with charged particles. Normally, this layer is relatively calm. But the aurora is caused by a storm of energetic particles from the Sun hitting the ionosphere, creating intense turbulence and swirling pockets of dense plasma. For a GPS signal passing through this chaos, it’s like trying to travel through those ripples in the pool. The smooth radio wave gets jiggled and distorted, messing up the precise timing information that receivers on the ground need to calculate your position. This study focused on phase scintillation, where the signal’s rhythm gets scrambled, rather than its volume.

The Northern Lights are a beautiful result of Earth’s magnetic field protecting us from the solar wind. But sometimes, that interaction gets explosive. An auroral substorm is a dramatic energy release in Earth’s magnetic tail, like a magnetic short-circuit. This process blasts a huge amount of particles into our atmosphere, creating the most intense and rapidly moving auroras. This study proves it’s these violent events that cause the worst problems for GPS. The researchers also saw that polar cap patches—floating clouds of dense plasma—drifted into the auroral zone just as the substorm hit. When the intense auroral energy slammed into these patches, it created a super-turbulent region that caused the most extreme signal scrambling. This shows a direct chain of events: a disturbance in Earth’s magnetic field creates a substorm, which supercharges the aurora, which then disrupts our vital navigation technology on the ground.

This shows that severe irregularities in the nightside ionosphere can be highly localized.
— Kjellmar Oksavik, Co-author

To connect the aurora with the signal problems, the science team used a clever combination of instruments. They had a network of special GNSS receivers in the Svalbard archipelago that could measure scintillation 50 times per second. This gave them a high-definition view of the signal disturbances. At the same time, they used All-Sky Imagers—essentially fisheye cameras pointed at the sky—to film the aurora’s every move. By layering the known positions of the satellites onto the all-sky images, they could see exactly which signals were passing through which parts of the aurora at any given moment. This allowed them to prove, without a doubt, that the most severe scintillation happened *only* when a signal’s line of sight went directly through the brightest, poleward-moving auroral arc. This multi-instrument approach turned a correlation into a cause-and-effect discovery.

Q: Could my phone’s GPS stop working during an aurora?
A: It’s very unlikely in a city or at mid-latitudes. This severe effect is mostly confined to high-latitude regions like the Arctic and Antarctica. However, for aircraft, ships, and scientists in these regions who rely on high-precision GPS, this type of interference can be a serious problem.

Q: Are all auroras bad for GPS?
A: No, not at all. Faint, slow-moving auroras have very little effect. The problems occur during intense, energetic events called substorms, which create rapidly changing structures in the ionosphere that scramble the signals.

Q: What’s the difference between phase and amplitude scintillation?
A: Think of it like a radio station. Amplitude scintillation is when the signal gets weaker or stronger, like turning the volume up and down. Phase scintillation is when the timing or rhythm of the signal gets messed up. This study found the aurora mostly messes with the signal’s rhythm.

Q: Why is this research important?
A: As human activity increases in the Arctic—for shipping, aviation, and research—our reliance on GPS is growing. Understanding exactly when and where these signal blackouts can occur helps us build better, more resilient navigation systems and create more accurate space weather forecasts to warn users.