How the strong solar storm could impact GNSS

May 14, 2024  - By
NASA’s Solar Dynamics Observatory captured this image of solar flares on May 11, 2024. The NOAA says there have been measurable effects and impacts from the geomagnetic storm. (Photo: Solar Dynamics Observatory)

NASA’s Solar Dynamics Observatory captured this image of solar flares on May 11, 2024. The NOAA says there have been measurable effects and impacts from the geomagnetic storm. (Photo: Solar Dynamics Observatory)

Earth is experiencing a severe solar storm causing concern for those responsible for power grids, communication systems and satellites.

The National Oceanic and Atmospheric Administration (NOAA) has reported measurable effects and impacts from the geomagnetic storm that has been visible as aurora across vast swathes of the Northern Hemisphere. As of May 12, 2024, NOAA had seen no reports of major damage.

There has been some degradation and loss to communication systems that rely on high-frequency radio waves, NOAA told NPR, as well as some preliminary indications of irregularities in power systems.

“Simply put, the power grid operators have been busy since yesterday working to keep proper, regulated current flowing without disruption,” said Shawn Dahl, service coordinator for the Space Weather Prediction Center at NOAA.

“Satellite operators are also busy monitoring spacecraft health due to the S1-S2 storm taking place along with the severe-extreme geomagnetic storm that continues even now,” Dahl added, saying some GPS receivers have struggled to lock locations and offered incorrect positions.

As NOAA warned, the Earth has been experiencing a G5, or “extreme,” geomagnetic storm. It is the first G5 storm to hit the planet since 2003, when a similar event temporarily knocked out power in part of Sweden and damaged electrical transformers in South Africa.

As of May 13, NOAA’s Space Weather Prediction Center said that a G3, or “strong,” geomagnetic storm warning was in effect until 2 a.m. ET. While stronger storms are no longer likely and conditions are expected to “gradually wane” throughout the day, the center said in its forecast that moderate to strong geomagnetic storms are “likely” on May 13, as are minor storms on May 14.

The center also said that “solar activity is expected to be at high levels” with a possibility of more solar flares, or bursts of electromagnetic radiation from the sun.

The update came as another X-class solar flare was recorded. X-class flares are the strongest class of these solar bursts, and the latest was recorded as “moderate.”

Flares of this magnitude are not frequent,” the center said. “…Users of high frequency (HF) radio signals may experience temporary degradation or complete loss of signal on much of the sunlit side of Earth.”

Northern lights in unusual places

On May 12, people from all around the world shared photos of a dazzling display of the Northern Lights, which were visible in Russia, Scandinavia, the United Kingdom, continental Europe and some even reported seeing the aura as far south as Mallorca, Spain.

In the United States, the NOAA center shared that the storm-induced auroras were visible as far south as Northern California and Alabama.

The source of the solar storm is a cluster of sunspots on the sun’s surface that is 17 times the diameter of Earth. The spots are filled with tangled magnetic fields that can act as slingshots, throwing huge quantities of charged particles toward our planet. These events, known as coronal mass ejections, become more common during the peak of the Sun’s 11-year solar cycle.

While the storm has proven to be large, predicting the effects of such incidents can be difficult, Dahl said.

The world has grown more reliant on electronics and electrical systems. Depending on the orientation of the storm’s magnetic field, it could induce unexpected electrical currents in long-distance power lines. Those currents could cause safety systems to flip and trigger temporary power outages in some areas.

The storm caused some navigational systems in tractors and other farming equipment to break down, suppliers and farmers told the New York Times.

Farmers have become dependent on equipment that utilizes GNSS and other navigation technology to help them plant more effectively — a practice known as precision agriculture. However, some of these operations in the Midwest, as well as in other parts of the United States and Canada, came to a temporary halt.

How it affects the ionosphere

The storm will also likely disrupt the ionosphere, a section of Earth’s atmosphere filled with charged particles. Some long-distance radio transmissions use the ionosphere to “bounce” signals around the globe, and those signals can be disrupted.

The particles may also refract and otherwise scramble GNSS signals, according to Rob Steenburgh, a space scientist with NOAA. Those effects can linger for a few days after the storm.

The storms can bring on ionospheric scintillation, which refers to rapid fluctuations in GNSS signal strength and phase due to localized irregularities in the electron density of the ionosphere resulting from solar activity. Scintillation adversely affects GNSS positioning, particularly around the geomagnetic equator after local sunset.

Similarly to Dahl, Steenburgh said that it is unclear just how bad the disruptions will be. While we still depend on GNSS, there are also more satellites in orbit. Moreover, the anomalies from the storm are constantly shifting through the ionosphere like ripples in a pool. “Outages, with any luck, should not be prolonged,” Steenburgh said.