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Posts Tagged ‘Lucy Hancock’

What could we learn from the rings?

There is now a weather forecast based on a simulation of the relationship between the Earth, the Sun, and the hypothesized Earth rings. The simulation is complex and hard to watch; that’s why I saved it until I could lay out some background. Today I would like to explain what it might contribute to a weather forecast, but let me begin by reiterating that this is a hypothesis, not a prophecy. There are many influences on weather; this is a hypothesis that Earth rings could be one of them, and such rings would be more important during years of quiet sun; in fact, the better I understand them, the more important they seem so: disclaimer finished.

Of course, the rings won’t change the mountains near you; they won’t stop “lake effect” snow; they won’t make the Earth revolve backwards around the Sun or shift the equator or stop the jet stream (though they might guide the Hadley cells…) But after all the things we can’t change have been taken into account, there’s still a lot of weather that still takes us completely by surprise and seems to have no cause at all. Some of it fits into the ring model. It’s worth looking to see how much.

Here are a few things to help you watch the simulation.

Where am I?

First of all, notice the position of our northern hemisphere. The simulation begins in January, and you are lobserving Earth and its rings from the Sun. Jan 1 is very close to the winter solstice, and the South Pole is in full view; the North Pole is in back.

Second, notice that there are two sets of rings, two discs, one equatorial, and the other tilted slightly across the equator. The tilted set slips from side to side each month. That’s because it’s the Phoebe ring, and its center is actually the gravitational center of the Earth-Moon system, rather than the center of the Earth. As the Moon goes around the Earth each month, the uptilt of the disc follows it and so does the center of rotation. Watch how the Phoebe rings slip from left to right and back again because this will help you distinguish them from the equatorial rings.

Third, because the Earth is tilted 23° with respect to the sun, and because your point of view in this video is as if you stood on the Sun, the tilt of the equatorial ring system also shifts, making the rings very confusing sometimes. Majestic, but confusing!

Key: the equatorial disc of rings shifts its angle but not its center; it tilts, but it does not slip from side to side.

The equatorial ring:

  1. In January, you are looking at the rings from the south, so they cast their shadows north.
  2. In spring, you have one day (March 20) of looking at those rings edge-on. This is always a possible storm time, but noticing the heaviness of the Phoebe ring suggested that it would also be cold, and that this cold would persist for a while. See below. Notice also that the North Pole is coming into view.
  3. In summer, the equatorial ring shadow is cast south as you look at the disk from the north. An equatorial ring system would make the winters colder but would not affect the summers. Here is the North Pole in full view.
  4. On September 22, there is another day of edge-on for the equatorial rings, and then they begin again to cast their shadows north again; if the equatorial rings are heavy, they will make the winter colder, but they will never affect the summer.
  5. Because both sets of rings are sometimes tilted, their motions can be very confusing. Note that the equatorial rings are the ones that do not slide from left to right.
  6. As winter progresses, the equatorial disk gradually spreads out across the background of the Earth, until it is fully opened around Dec 22; then it begins to fold back again.

The Phoebe ring

  1. As the simulation begins, the Phoebe ring is casting its shadow north along with the equatorial ring.
  2. As you approach May 7, the Phoebe ring is folding up. Its increasingly heavy and localized shadow might be expected to cause storms, which would eventually move southwards with its maximum shadow. This is the reason for the forecast of a rough April, which is certainly being fulfilled in South Dakota. (The ring forecast was made January 1.)
  3. May 7, the Phoebe ring is edge-on to the Sun, and everything north of the tropics is out of its shadow.
  4. After that, its shadow falls south, which mostly affects the southern hemisphere but also the equator, at least for a while. In any case, it leaves the North Temperate zone clear. All summer, you see the Phoebe ring sliding from right to left, from left to right, but always with its shadow southward. That’s why the ring forecast is for a relatively mild and warm summer. For us. For the US, and also for Europe and the northern hemisphere generally. At the same time, it could mean a colder winter for the southern hemisphere, which faces both rings from May to September.
  5. On October 30-31, the Phoebe disc of rings is edge-on. Again, this deep shadow could cause storms, and at the same time, the equatorial rings have been spreading chill northwards all month. From then on, the northern hemisphere has both sets of shadows, with the Phoebe rings swinging majestically from side to side, but continuing to supply a north-falling shadow. It is hard to say exactly how the two discs will interact, especially since we don’t know their detailed structure – we don’t know which rings are heaviest and how far out.

But it looks cold. And if you watch the simulation at the youTube site, there is a longer and more detailed forecast underneath. It’s from Lucy Hancock, the architect of this whole

There is also a forecast for next March being harsh like this April, but I don’t have the simulation for that. That’s when the Phoebe ring-shadow falls north again, not on the same date as this year, but earlier.

All of this is based on the work of Lucy Hancock, who has her own blog on earthrings.

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