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Engadget's says:

A recent batch of SpaceX’s Starlink internet-beaming cubesats met with tragedy on February 3rd when a 49-member cohort of the newly-launched satellites encountered a strong geomagnetic storm in orbit.

“These storms cause the atmosphere to warm and atmospheric density at our low deployment altitudes to increase. In fact, onboard GPS suggests the escalation speed and severity of the storm caused atmospheric drag to increase up to 50 percent higher than during previous launches,” SpaceX wrote in a blog update last Wednesday. “The Starlink team commanded the satellites into a safe-mode where they would fly edge-on (like a sheet of paper) to minimize drag.” Unfortunately, 40 of the satellites never came out of safe mode and, as of Wednesday’s announcement, are expected to, if they haven’t already, fall to their doom in Earth’s atmosphere.

Question: How (exactly) does "onboard GPS" suggest "escalation speed and severity of a storm caused atmospheric drag to increase up to 50 percent"? I know that GPS signals can be used to measure precipitable water vapor, but how can it be used to measure atmospheric properties like increased drag compared to other launches?

Related to atmospheric water vapor measurements via GPS signals

uhoh
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    Position vs time? – Organic Marble Feb 17 '22 at 01:45
  • @OrganicMarble Hmm... GPS and a simple computer program could calculate rate of loss of altitude and/orbital energy versus current altitude, but "onboard GPS suggests the escalation speed and severity of the storm caused..." it would be a different matter. Maybe it's a combination of imperfect wording of a SpaceX statement and my literal reading of it that's got me here, rather than a heretofore unknown capability of GPS to measure the "escalation speed and severity of (a solar) storm"? – uhoh Feb 17 '22 at 02:27
  • @OrganicMarble so maybe it just has a simple GPS-based "drag-o-meter" and any connection to the storm is in the eye of the beholder rather than in the Starlink itself? – uhoh Feb 17 '22 at 02:30
  • If you predicted what it should be, and GPS location vs time tells you what it actually is, methinks you can back out the drag. Might not even need the prediction. – Organic Marble Feb 17 '22 at 02:35
  • @OrganicMarble yes sure agreed etc. If that's the only functionality that SpaceX is talking about in their blog, and GPS is not used to determine anything about the solar storm itself nor the cause of the drag, then I've misread SpaceX's sentence or the sentence is sub-optimally written (or both). In that case this question is about a sentence and not about spaceflight and should self-destruct. – uhoh Feb 17 '22 at 02:40

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