Can we sequester methane by pumping air through soil?

[Al_]

Methanotrophs already exist in most soils. If we expose them to more methane, will they eat more? A solar powered fan blowing air down a tube that ran along under soil, with lots of small holes along its length - would that reduce the methane in the air?

As a second part to the question, does anyone know an inexpensive way to measure the effect? Sensors that can measure parts per million are only a few dollars, but ones that can detect parts per billion are very expensive. And the air contains only 1 or 2 parts per million. Is there a more basic way?

 

[rootone]

I can't see why methane capture from the atmosphere is a worthwhile project,
since the amount of methane in the atmosphere is very little, although an increase in methane is not desirable

 

[olivermsun]

Might be more feasible to capture methane from the places it leaks into the atmosphere and/or try to increase oxidation in the atmosphere.

 

[TeethWhitener]

I can't see why methane capture from the atmosphere is a worthwhile project,
since the amount of methane in the atmosphere is very little, although an increase in methane is not desirable

Methane levels are at 1.8 ppm and methane has 30x the global warming potential of CO2. So it’s like having an extra ~50ppm of CO2 in the atmosphere (the current level of CO2 is ~400ppm). So methane accounts for ~10-20% of observed radiative forcing (back of the envelope). Decreasing methane levels isn’t a bad idea to combat climate change.

Edit: from Wikipedia (with a citation) a bit of a technical critique on the forcing potential metrics used: “...the benefits of rapid direct reductions of methane are also thought to be substantially obscured by this choice of warming time horizon [100 years] for methane.”

 

[256bits]

Methanotrophs already exist in most soils. If we expose them to more methane, will they eat more? A solar powered fan blowing air down a tube that ran along under soil, with lots of small holes along its length - would that reduce the methane in the air?

As a second part to the question, does anyone know an inexpensive way to measure the effect? Sensors that can measure parts per million are only a few dollars, but ones that can detect parts per billion are very expensive. And the air contains only 1 or 2 parts per million. Is there a more basic way?

You might like to do some background investigation on this subject for your own curiosity, and check the validity of a project.
Are there other creatures in the soil that produce methane ( ie decaying organic material )
What is the % makeup of methane in the soil?
Would blowing atmospheric air into the soil increase or decrease the makeup of methane in the soil? - in other words could the air dilute the soil methane?
Would blowing concentrated methane into the soil have a more desirable effect, or less?
If an effect is noted, how much?
Then how much air, along with soil, would be needed to have an affect upon the general % of atmospheric methane?

I don't have the answers, but some of the things I would look at.

 

[Al_]

You might like to do some background investigation on this subject for your own curiosity, and check the validity of a project.
Are there other creatures in the soil that produce methane ( ie decaying organic material )
What is the % makeup of methane in the soil?
Would blowing atmospheric air into the soil increase or decrease the makeup of methane in the soil? - in other words could the air dilute the soil methane?
Would blowing concentrated methane into the soil have a more desirable effect, or less?
If an effect is noted, how much?
Then how much air, along with soil, would be needed to have an affect upon the general % of atmospheric methane?

I don't have the answers, but some of the things I would look at.

If I can measure the air coming out, it covers the first points. That is, if it comes out with less methane, it doesn't much matter what is going on inside.
I can't blow concentrated methane into the soil, I'm trying to reduce atmospheric methane, and I don't think I can reasonably concentrate it.

How much air? Well, all of it? Half of it? A lot of pumps.
ok, i did some rough math.
A regular ventilation pump/fan of 100m^3 per hour
Volume of atmosphere if taken to sea level pressure = 4 x 10^18 m^3
So, 5 x 10^12 such could pump it all in a year. 5 Trillion fans. Need bigger fans.
We can get bigger fans, but the more important question is, how much soil do you need for this flow rate?