Tidal locking question

[llama]

I should start by saying my understanding of geology and astronomy is at a high school level at best. I don't need the answers to be a hundred percent accurate; I write fiction. And if movies like THE CORE can work for the average Joe, than anything can.

What I'm looking for in an answer is: How can I make this farfetched event seem plausible to people who know nothing about science and are just reading for enjoyment?

So, my question is about tidal locking. I need it to happen to Earth. If this happened, is there any way life could still be sustained? Basically, I want half the planet to always be dark while the other half is light. And I can't have everyone dying off. This is a thriller, not sci-fi. The basis for this book isn't about the global effects. It's about the chaos that ensues on the dark half.

So, any help with this would be greatly appreciated.

[pederv]

I think I saw this on the History channel or Discovery or something. One of those "What would happen if...". This one was "What would happen if the Earth stopped spinning". The oceans were no longer under the influence of centrifugal force, so they migrated to the poles where they got over 50 miles deep. Some areas of the exposed land were so high that they extended into the upper atmosphere. The surviving humans migrated to the twilight zone next to the ocean.
There were a few holes in the premise, like if the Earth stopped spinning wouldn’t the core stop spinning also? Then we’re back to The Core.

[KeithBC]

If I understand correctly, you are not talking about a situation where a planet has been tidally-locked for millemia. You want it to happen fairly suddenly, right?

The big problem is going to be where does the angular momentum go? You can probably sweep this problem under the rug in a work of fiction, but you still have to think about how quickly it goes wherever it goes. The timing will affect your story line.

If it happens too fast, you are going to get all kinds of mechanical problems. Everything on the surface is moving at several hundreds of kilometres per hour. If you suddenly stop the foundation of a house, the roof is going to want to keep going - goodbye house. The same thing happens to the rocks in the earth's crust: How suddenly do they stop,and how even is the process? Expect earthquakes and major geological mayhem.

Assuming you have survived the transition, you will have to think about weather and climate. Most weather is the result of the sun's heat being transferred by the earth's rotation. Now, you have totally changed that pattern. Over the months following the transition, new weather patterns will develop. Surface winds will blow from the dark side to the bright side. High altitude winds will blow the opposite direction.

The middle of the bright side would get very hot, and the middle of the dark side would get very cold. Temperatures at the terminator (the line between bright and dark) would be moderate, but it would be permanently stormy due to the winds blowing towards the bright side.

The difference between summer and winter would be minimal. Summer would occur all over the globe in January, and winter wold occur in July. You might or might not notice the difference.

[llama]

Excellent answers! Exactly what I need. Thanks so much!

[llama]

Also, isn't tidal lock different than the Earth no longer spinning? I mean, if Earth was tidal locked, doesn't that mean it would then take 365 days for one rotation, instead of 24 hours?

I'm asking because I want to create a scenario where half of Earth is always dark, not just for half a year (as it would be if Earth stopped spinning). Thanks!

[Space Jockey]

Spin-orbit coupling with Sol I think you mean... one rotation per year.



,

[KeithBC]

Also, isn't tidal lock different than the Earth no longer spinning? I mean, if Earth was tidal locked, doesn't that mean it would then take 365 days for one rotation, instead of 24 hours?

I'm asking because I want to create a scenario where half of Earth is always dark, not just for half a year (as it would be if Earth stopped spinning). Thanks!

Correct. Tidally-locked means one rotation per year in the same direction as the orbital revolution.

[jenniferchristine]

I don't hold out much hope for the three survivors who happened to be cave diving at the time.
I think stopping the core would result in collapse of the magnetosphere and consequent stripping of the atmosphere by solar winds.

[KeithBC]

I don't hold out much hope for the three survivors who happened to be cave diving at the time.
I think stopping the core would result in collapse of the magnetosphere and consequent stripping of the atmosphere by solar winds.

Not to mention frying those survivors with radiation when the VanAllen belts fall down to ground level.

[erb...]

Think its fair to say, that all life on the planet would be no longer if the planet even began to slow, on saying that bacteria, sea monkeys, cockroaches and the taxman may all survive.