Sea level conundrum.

[notty ash 372]

Isn't Everest still growing? Thought I read it somewhere last year.

[MargieH 7,615]

notty ash, I believe you are right that Everest is still being pushed upwards, so maybe that will keep the height the same as it is now, as the sea level rises! Whatever..... Everest is high and in the realms of probability I'm 99.9999999... % sure I'll never climb it!

[NewBasfordlad 3,599]

Got invited to be a 'base camp' porter back in early 1971 for a 1972 climb.

Married June 71 SWMBO didn't want me to go so that was the end of that. Still wonder to this day if I could have hacked it...........

[MargieH 7,615]

Just had a strange thought ..... if the mountains are still being pushed UP, won't that make the Indian Ocean/Pacific deeper, thus allowing the warmed oceans more room so they won't rise so much? Or have I got the mechanics of plate movements wrong?

[Ayupmeducks 1,730]

Then there's the mid Atlantic Ocean rift, which is widening all the time, earth getting larger??? If so, the oceans should be dropping in depth.

[MargieH 7,615]

Never heard these theories before! Do you think we've discovered something important ? ...... probably not, as the experts on plate tectonics would have already thought of it I suppose

[Ayupmeducks 1,730]

The Atlantic rift is a fact, not a theory Margie, on radar scans of the ocean floor you can clearly see that the rift is a living "scar" growing west and east, like a cut on your skin.

[MargieH 7,615]

Ayup, sorry, we seem to be talking at cross-purposes. I know the Atlantic rift is a fact - I was referring to the sea bed getting wider/deeper thereby causing the sea level to drop!

[mercurydancer 1,104]

Margie

The pacific is slowly descending westwards along the "ring of fire" or pacific rim. The pacific is therefore getting deeper, although there comes a point where it is absorbed by the mantle of the earth.

[Beduth 202]

Yes, well you can blame Johnny Cash for that.

It was all that curry he used to eat.

[Compo 10,328]

The Mid-Atlantic Ridge is a "constructive" zone. That is to say, an area where magma is rising through a crack in the Earth's crust and as it does so it forces the Earth's tectonic plates apart. The ridge never really gets any wider but does two things: 1. It builds up material making more ocean floor and 2. As it builds up the ocean floor it puts pressure on the tectonic plate and tries to force the continents away from each other. However, where an ocean plate meets a continental plate one gets a reaction. The ocean plate is more dense than the continental plate and thus when they collide, the ocean plate dives beneath the continental plate, pushing up the continental plate causing mountains to form. This is how the Andes and Himalayas have come into being. Both are still rising too. Another effect of this "Subduction" is volcanic activity and earthquakes as the subducting material becomes molten under pressure. Hence, you should never build a nuclear power station on a subduction zone - like they did in Japan!

[mercurydancer 1,104]

compo is exactly right. However, for sea levels there is another effect called albedo. Snow is white. Sea is not white. The ground in general is not white (unless covered by snow)

Now sunlight hitting white surfaces gets reflected back into the atmosphere, oddly enough keeping it warmer. If the ground or sea does not have ice, the heat is absorbed and the land and sea gets warmer. What the results of this actually are is not possible to say, beyond that there will be climate change.

Clever people are trying to work out the annual albedo. USA and Canada had more snow than average, Russia had less.

[Compo 10,328]

They used to say that the Albedo of Earth was 4.5.

[Chulla 4,946]

The Earth's albedo is 0.39. Somewhere on the music thread is a Vangelis recording that tells you this.

[Ayupmeducks 1,730]

I knew an albedo once, he was pretty pale........I'm off.>>>>>>>>>>>>>>>>>>>>>>>>>>

[Compo 10,328]

Johnny Winter was an albedo too.

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