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Author Topic: Can we store excess sea water underground?  (Read 1243 times)

Offline thedoc

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Can we store excess sea water underground?
« on: 18/05/2016 09:46:26 »
Why can't we replace the space from which we have extracted crude oil with seawater in an attempt to solve the rising sea level crisis? With the amount of oil we extract surely it could make a difference seeing as the immediate threat is posed by greenland melting and causing sea levels to rise 6-7m? although since water moves in to replace the oil we take out the process would probably have to be done immediately and be extremely complex.
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« Last Edit: 18/05/2016 09:46:26 by _system »


Offline evan_au

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Re: Can we store rising sea water where we once stored oil?
« Reply #1 on: 20/01/2016 20:15:53 »
I see a problem with energy balance.
In the early days of oil exploration, it took 1 barrel of oil to extract 100 barrels of oil. Fairly efficient, you might say.

If we are going to pump sea-water underground, that will take energy - probably much of it from fossil fuels.

But the "easy" and "accessible" sources of oil have now been largely consumed. Recently, the US & Canadian governments were seriously considering using tar sands to provide oil to the USA. This source is thought to consume about 30 barrels of oil to deliver 100 barrels of oil. That is really inefficient, and will result in more CO2 being emitted.

If we look at the cause of sea level rise, it is not the pulse of increased energy output that humans have produced from their beeswax candles, wood stoves, or oil, coal and nuclear power stations. That is a mere drop in the bucket compared to the solar radiation which arrives on Earth every day (and leaves every night), or even the geothermal energy which comes out of the Earth every day.

It is the fact that we have put extra CO2 into the atmosphere, while chopping down (and often, burning) the trees that would have absorbed some of it.

The melting is caused because the small increase in CO2, from 350 ppm to (now) slightly over 400 ppm holds in a tiny fraction of the Sun's heat which escapes overnight. For every Joule that humans generate from fossil fuels, the Sun injects more Joules into the atmosphere and even more into the oceans and ice sheets.

So the solution is not to use fossil fuels to refill the old oil reservoirs, but for people to vote with their roof and install solar panels etc, which will at least slow down the rate of heat retention and sea-level rise.

Offline Tim the Plumber

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Re: Can we store rising sea water where we once stored oil?
« Reply #2 on: 26/02/2016 14:14:56 »
The total oil we have ever used is less than 100 km≥ ( I have assumed a density of 1, yes I know it's wrong but...).

That would be less than a third of a milimeter of sea level rise if you put that much back down into the ground.

The world's oceans are really big!!! I mean really really big!

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Re: Can we store rising sea water where we once stored oil?
« Reply #2 on: 26/02/2016 14:14:56 »


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