SCOTT DETROW, HOST:
If you spent some time outside last night, maybe away from any big city lights, you might have been treated to the pinks and oranges of the aurora borealis. It is caused by charged particles shot out from the sun that hit the Earth's magnetic field and crash against the upper atmosphere. That's what makes all the shimmering colors. The last few years have seen a large number of these kind of storms. Shawn Dahl, a forecaster at the National Oceanic and Atmospheric Administration's Space Weather Prediction Center, had a busy night tracking all of this. Welcome to the show.
SHAWN DAHL: Yeah, thank you for having us. Happy to be here.
DETROW: Let me just start with this. I feel like this is, like, the third conversation we've had on ALL THINGS CONSIDERED about these big geomagnetic storms in the last year or so. Is this happening more frequently or are we just paying more attention?
DAHL: Both, actually - we are in solar maximum right now. That is when we see more of this type of stronger activity. And it's also that people are aware of it more now because of the activity. People have been looking up, and it's not just from the aurora. It's been total solar eclipses and comets. And there's both factors playing in here.
DETROW: I like that phrase solar maximum. How much longer will it last?
DAHL: Typically, the solar cycle, which is part of solar maximum, you go from minimum to maximum and back down to minimum. Now solar maximums generally last several years, and then you start to slowly trail down. So even though we're starting to see signs of maybe coming out of solar maximum, we can still see activity like this from time to time throughout this year and probably even in 2027.
DETROW: Oh, OK. That's good to know. How big was this one compared to the other recent ones we've been talking about and hearing about?
DAHL: Well, there's two parts to that one. As far as how big the geomagnetic storm was, we did reach G4 severe levels. That's near the top end of our scale. We came close to hitting the top end of our scale, a G5 extreme level, but we didn't quite get there. But the interesting thing about this storm is even though it wasn't a prolific aurora producer across North America - 'cause things weren't favorable most of the overnight hours; it changed later on, so the western part of the U.S. really did get to see something more - it was a very strong magnetic event that passed over Earth, the strongest many of us have seen here in 20 to 30 years.
DETROW: And especially in this world where we all live off of satellite-based technology, that can cause big problems, right? Were there any effects last night?
DAHL: We are starting to try to begin to dig into that. It'll take some time to get anybody who's willing to report impacts from the industries and sectors that could be impacted by these satellite operators during the geomagnetic storm, the intensification periods of that. We do know there were GPS issues for aviation. We've seen some reports, which makes sense. GPS can become less accurate during these storms, especially precision systems that drive them. And as far as the electric power grid goes, we are unaware of any impacts at this time, but that will take some time before they're able to tell us anything that might have unfolded there. But we did give them a very advanced notice. We talked to them early yesterday morning, a number of hours before that CME ever even arrived here at Earth.
DETROW: How easy is it to do your job? I mean, how easy or difficult is it to accurately predict these storms, when they're flaring up, when there might be issues like that?
DAHL: Yeah, it's very hard. Space weather forecasting is a tough business. You have to be willing to take the bumps and the bruises that go along with it. You know, most of us in this profession have been meteorology side of the business for a long time, and we're well aware of how good that's become - forecasting, you know, winter storm, seven days out. Man, when it comes to space weather, we're nowhere close to that. You know, we could have a quiet forecast or a low-level event forecast going on, and then suddenly it changes in one to two days out because of something like that CME that blasted from the sun back on Sunday.
DETROW: We're talking about where things are right now, or we're talking about these 11-year cycles. I'm curious what your hopes are for the next time we're in solar maximum in terms of where your industry is and what sort of resources and technology are around to better predict all of this.
DAHL: Yeah, for the next solar maximum, you know, 11 or so years from now, we hope that there'll be another spacecraft available. We know one is in the plans. And that spacecraft could potentially be at a very critical location for us, and that would be almost a side view of the sun of what's rotating into Earth view. There's been a lot of exploratory science missions that are going to derive a lot more science. It's going to increase our understanding of how these things work, so we can do even a better job of predicting them and have more tools at our disposal for the next solar maximum.
DETROW: That's Shawn Dahl, a space weather forecaster with NOAA. Thank you so much.
DAHL: You're very welcome. Thanks for having us.
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