Openai/696c8354-b540-8006-aeef-06dc925f7283
This conversation was exported from ChatGPT[1]
gpt-5-2[edit | edit source]
User: Please see two images attached.[edit | edit source]
Please see two images attached. I have observed this phenomenon for the last year. When our Aurora metrics stay mostly equal, the Ovation stretches further south when it hits Canada than when it's over Ireland. Since making my Ovation model and overlaying photo and visual rings it has made this more apparent. Can you explain why this phenomenon is happening?
Assistant: What you’re seeing is real and well-known.[edit | edit source]
What you’re seeing is real and well-known. It is not a bug in your model or rings. The auroral oval is not latitude-symmetric, and Europe is systematically disadvantaged compared to North America.
Here’s why, stripped of fluff.
1. The auroral oval is centred on the geomagnetic pole, not the geographic pole[edit | edit source]
The North geomagnetic pole is currently located in northern Canada, not near Greenland or Europe.
That single fact explains most of what you’re observing.
- Canada sits closer to the center of the auroral oval
- Ireland and Europe sit farther from it, even at similar geographic latitudes
So when the oval expands under similar KP / Bz / power:
- Canada is hit earlier and deeper
- Europe only gets the outer skirt
This makes the oval appear to “bulge” southward over Canada but not over Ireland.
2. Longitude matters as much as latitude (this is the key mistake most apps make)[edit | edit source]
Aurora visibility is not a simple “latitude threshold”.
It depends on magnetic latitude, which is warped by Earth’s tilted, offset magnetic dipole.
Approximate comparison:
- Manitoba / Ontario (~50–55°N) ≈ 60–65° magnetic latitude
- Ireland (~53°N) ≈ 54–56° magnetic latitude
That is a huge difference in auroral terms.
So even if KP and hemispheric power are identical:
- Canada is magnetically much closer to the oval
- Ireland is magnetically much farther south
Your rings are correctly exposing this.
3. The oval is not circular — it is distorted and compressed over Europe[edit | edit source]
Several physical effects reinforce this asymmetry:
a) Magnetic dipole offset[edit | edit source]
Earth’s magnetic field is:
- offset from the center
- tilted ~11°
- asymmetric between longitudes
Result:
- Oval is fatter and lower over North America
- Oval is thinner and higher over Europe
b) Magnetospheric compression[edit | edit source]
Under solar wind pressure:
- The nightside oval expands unevenly
- Expansion preferentially pushes into North America first
This is why:
- Canada often gets aurora at KP 4–5
- Ireland often needs KP 6+ for the same depth
4. Viewing geometry makes Europe look worse even when aurora exists[edit | edit source]
Even when aurora is technically present over Ireland:
- It is usually lower on the horizon
- Emission height (~100–120 km) + curvature means: - Canada sees aurora higher in elevation - Ireland sees it flatter and weaker
Your photo vs visual rings are correctly capturing this:
- Canada intersects the oval at better elevation angles
- Ireland intersects it at marginal or sub-visual angles
Hence:
- “Metrics look equal, but Europe gets nothing”
That’s expected.
5. Why your observation became obvious only after adding rings[edit | edit source]
Before:
- Flat KP maps hide longitude bias
- Most apps assume symmetry (incorrectly)
After adding:
- Elevation-aware rings
- Location-specific evaluation
You removed the lie.
Your model is showing true auroral geometry, not marketing aurora.
Bottom line (plain truth)[edit | edit source]
- The auroral oval does stretch further south over Canada than over Ireland
- This is due to: - Geomagnetic pole location - Magnetic latitude differences - Oval distortion and compression - Viewing elevation geometry
- Your Ovation overlay + rings are correct
- Most aurora apps are over-promising Europe
If anything, your model is more honest than what users are used to seeing.
If you want, next step would be:
- Explicitly labeling “Magnetically favoured regions”
- Or adding a subtle note like: “Europe requires stronger activity than North America at the same latitude.”
That would head off confusion — and it would be scientifically accurate.
References[edit | edit source]
- ↑ "Auroral Oval Asymmetry". ChatGPT. Retrieved 2026-01-20.