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According to this Discovery News video about Centralia Pennsylvania and other underground coal fires, there are many smouldering underground coal reserves making the land above it uninhabitable to humans.

One possible solution I thought of for extinguishing an underground coal fire might be to invent the technology to affect weather patterns and then create a continuous rainfall overhead so the water will drain down to the coal putting it out.

However, it's a very risky for people to make any big change to the Earth without first getting a research group to very carefully research whether it might cause a nasty problem later that they didn't think of. For example, maybe if every time a coal reserve catches on fire, people put in out, then the earth will start producing coal faster than it's getting depleted by natural process and eventually it will have such a huge buildup of coal that if a it catches on fire and doesn't get put out right away, it will grow too big to be able to put out and will then spread all over the entire continent.

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closed as unclear what you're asking by gansub, Fred, Daniel Griscom, Pont, Aabaakawad Nov 26 '15 at 4:16

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  • $\begingroup$ the earth will start producing coal faster than it's getting depleted by natural process The time period required for producing coal is gigantic, so this fear is not necessary. $\endgroup$ – Jan Doggen Nov 19 '15 at 21:36
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    $\begingroup$ "to invent the technology to affect weather patterns" - good luck with that $\endgroup$ – Gimelist Nov 19 '15 at 22:44
  • $\begingroup$ I'm not seeing a question here. Except in the title. $\endgroup$ – Semidiurnal Simon Nov 19 '15 at 22:47
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There isn't a risk to putting it out other than the attempt failing, it is just impractical to do so once a large coal vein catches fire. You can read more about the Centralia, PA coal fire on wikipedia which sits on top of anthracite coal veins that have been burning for a little over 50 years and are likely to continue to do so for a few hundred years.

Your proposed idea of "inventing weather modification" is not practical. While we have the technology to seed clouds and produce localized rainfall this still depends on the amount of water vapor in the air. You can bypass evaporating water into the atmosphere, seeding clouds and raining and instead just pump water into the mines and flood them. That will be much more efficient at getting water into the mines.

So why don't they flood the mines? That too is not practical, and if memory serves me right, they did try that in Centralia. The problems are

  • Mines open into cave systems
  • Water can flow through very small openings
  • Coal needs only be hot and in the presence of oxygen to burn.

This means you'll need to keep the coal underwater, isolated from oxygen until you can dissipate all of the geothermal heat mass that has built up in the surrounding rocks from the burning coal. You'll also have to make the mine water tight in order to flood it. You'll also need a way to deal with your flood water evaporating and steam build up.

Faced with the realization that extinguishing these fires is impractical the decisions were made to abandon the towns. There was no real risk in putting the fire out, it just isn't practically possible to do so. The risk in letting the fire continue to burn was abated by evacuating the town permanently. Burning coal does not effect the production of new coal (that takes a long time on geological time scales) -- burning coal is a net reduction in coal mass, not a gain.


As an aside, the other problem with cloud seeding, specifically with the Centralia, PA case, is legal. Pennsylvania farmers were so concerned about the possibility of cloud seeding elswehere in the state depriving them of needed rainfall that in 1968 the PA state legislature passed "WEATHER MODIFICATION - REGULATING RAIN MAKING. Act of Jan. 19, (1968) 1967, P.L. 1024, No. 449" which means you'll need to convince the state to issue a license for your activities, which is not likely to be granted.

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Nice idea but the practicalities are impossible. There are parts of Indonesia which have out-of-control peat and coal fires which have been raging for years, and even decades, despite those areas receiving well in excess of two metres of rain a year. See for example: Whitehouse AE and Mulyana AAS, (2004) Coal Fires in Indonesia. International Journal of Coal Geology, 59, 1-2, pages 91-97. It's true that some of the fires burn out during particularly wet years, but the sting in the tail is that the heat of hydration of dry coal tends to reignite the coal again during the dry season. Be assured that if there was a simple economic solution, it would have been tried by now. Some not so simple solutions are under trial, such as smothering the fire with nitrogen foam.

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