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Permafrost is defined as
a ground, or medium, (including rocks, soils and organic matter) with a mean annual temperature less than 0 °C for at least 2 consecutive years.
The smooth appearance of the walls can be explained by understanding how permafrost works. Permafrost is characterized by an active layer, which is a layer normally at the surface which ...
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Let's look at this. A very large number of points for one question.
First, the solar system. We do not see any hydrocarbons in the inner solar system (Mercury to Mars). This is because in this region of the solar system, dissociation by solar UV rapidly destroys primordial hydrocarbons. This effect is much weaker further out.
Oil well 'replenishment' will ...
5
I found a great paper named Remote Sensing of Particulate Pollution from Space: Have We Reached the Promised Land? and collected some remote sensing instruments doing CH4 measurement in the chart below.
It contains the information about the satellite, orbit types, instrument and the data time-range.
Satellite Orbit Instrument Years
...
5
A good explanation is found at the University of Bourgogne site MODELING THE ABSORPTION SPECTRUM OF METHANE.
Although it is a small and simple molecule, its rovibrational spectroscopy is very complicated. This is mainly due to the high symmetry of this tetrahedral system (which leads to the existence of many degeneracies) and to its intricated vibrational ...
5
Rather than using the GWP as a ratio, they are expressing the GWP as compared to a release of $\ce{CO2}$ with equivalent radiative effects. To use their numbers use the mass they give you and a GWP ratio of 1 for that mass (as if it were carbon dioxide). From what I've seen for chemical industry sales and marketing literature it is fairly common that they ...
4
A friend of mine works at the Permafrost institute in Moscow and he and his colleagues generally support this idea. I think that edges were formed by falling pieces of soil and vertical walls were formed when big methane bubble that went off the deeper layers.
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What caused a centuries long freeze, the beginning of the current ice age. Yes we are in an ice age, as long as greenland and antarctica have large ice sheets we are technically in an ice age) Which in turn was caused by the movement of continents close enough to the poles to create permanent ice caps. the freezing of organic matter into permafrost is not a ...
3
The definition of a fossil is "evidence of past life preserved by geologic processes".
By this definition a coal bed is itself a fossil since it is the preserved organic matter from an ancient swamp. Oil and Natural Gas that are formed by the change of dead algae under the heat and pressure of being buried in the earth. These would also be fossils.
...
3
According to Role of methane clathrates in past and future climates,
Methane occurrences and the organic carbon content of sediments are
the bases used to estimate the amount of carbon currently stored as
clathrates. The estimate of about 11,000 Gt of carbon for ocean
sediments, and about 400 Gt for sediments under permafrost
regions...
So 400 ...
2
According to Howarth, et al. 2011, from 4 wells they sampled, flow back after hydraulic fracturing lead to a release of methane equal to 0.6-3.2% of lifetime production of the well. Fracking wells released methane equal to 3.6-7.9% of lifetime production from all sources, while non-fracking wells released 1.7-6.2% of lifetime production.
Petron, et al. 2014 ...
2
The 'natural causes' of global methane emissions are, as you indicate, mostly of biological origin. To some extent it depends upon what you regard as 'natural'. There are many and differing estimates of global methane generation, of which I list a summary below. Those in bold you may regard as abiological. Values are in Mega-tonnes per year released to the ...
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Your first two links don't seem to mention clathrates.
Much ado about methane says:
What methane are we talking about?
The largest methane pools that people are talking about are in sediments of the ocean, frozen into hydrate or clathrate deposits (Archer, 2007). The total amount of methane as ocean hydrates is poorly constrained but could rival the ...
2
The possible source of methane is biological, and that is what everyone is hoping for, but the more likely source is geological, produced by chemical reactions between rock and water deep underground and issuing though fissures to the surface. We are dealing with very small amounts here which are difficult to detect and measure with precision. Once out in ...
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Mass of Earth's atmosphere: $5 \times 10^{18} kg$
Concentration of methane in Earth's atmosphere: $1866 ppb$
Mass of methane in Earth's atmosphere, present day: $9.3 \times 10^{12} kg$ = 9,300,000,000 tons
If all those dead mammals were composed entirely of methane, they would increase the atmospheric concentration of methane by about 2%. They aren't, and ...
2
This question is addressed in a Nature paper on "Understanding the glacial methane cycle" (Hopcroft et al. 2017).
There conclusion is that changes in methane concentrations are driven by changes in the biosphere associated with the global temperature changes. The dominant factor is the reduction in methane emissions from wetlands in a colder climate. There ...
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Just a guess, not a specialist on the topic. Pleistocene was characterised by multiple glaciations and interglacial periods. The increase in CO2 concentration and the increase in temperature normally leads to thawing of large ares of permafrost and formation of swamp areas in its place. These swamps release methane in the same way they do today.
Obviously, ...
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how large would the leaks have to be to counteract the positive effects?
Trying a ballpark estimate ... biogas replaces natural gas. For simplicity let's assume the replacement is 1:1, one mole of methane from biogas* replaces one mole of natural gas. This also means that one mole of biomethane "saves" one mole of CO2.
Methane is about 25 times more ...
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Yes
It is one of most common compounds in the universe.
https://en.wikipedia.org/wiki/Methane#Extraterrestrial_methane
Which period of the early earth do you want to know about? the earliest atmosphere likely had less methane than now. http://science.sciencemag.org/content/308/5724/1014
But once life evolved methane rose.
http://www.minersoc.org/pages/...
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