Sentences with phrase «if methane hydrates»

He says that even if methane hydrates were resting beneath the Antarctic Ice Sheet, and they became destabilized and started bubbling methane up through the seawater to the surface, it would take hundreds of years for these methane reserves to have a detectable impact on global climate.

And there's the rub: If methane hydrates are like forests, then we don't understand the trees.

And I assume from the article that if the methane hydrate deposit is melting then the bottom water will have a high level of dissolved methane.

Not exact matches

«If the decomposition of the methane hydrate phase is fast enough, which depends on temperature, the methane gas in the aqueous phase forms nanobubbles,» said Saman Alavi, one of the lead researchers on the project.

Taken together, they also provide a potential explanation for the so - called memory effect — the fact that «aqueous solutions in contact with methane form solid methane hydrate at a much faster rate if they have already undergone a methane hydrate formation - decomposition cycle,» said Alavi, almost as if the hydrate «remembers» its previous state.

«If we have basic knowledge about the mechanical properties of methane hydrates, we can use this information so that we manage them properly,» Zhang said.

This is bad news for oil prospectors drilling in permafrost: if they encounter a pocket of hydrates, the released methane could rupture their drilling equipment.

In a paper published in the 2 November edition of Nature Communications, corresponding author Zhang and his colleagues describe how they used a computer simulation of two types of methane hydrates, monocrystalline hydrates and polycrystalline hydrates, to see what would happen if they were compressed or if pressures on the hydrates were suddenly released.

Even if engineers could construct a system to bring a load of hydrate to the surface before it disappeared, extracting the methane from the matrix of mud and rock would still present a problem.

«Our data suggest that even if increasing amounts of methane are released from degrading hydrates as climate change proceeds, catastrophic emission to the atmosphere is not an inherent outcome.»

If the pressure is too low or the temperature too high, the hydrates dissociate (break down), the methane is released and the gas can seep from the seafloor into the ocean.

And finally, what about Mark's questions (# 3) and other factors not discussed here — do all these effects re Arctic ice lead scientists to believe there is a greater and / or earlier chance (assuming we continue increasing our GHG emissions — business as usual) of melting hydrates and permafrost releasing vast stores of methane into the atmosphere than scientists believed before the study, or is the assessment of this about the same, or scientists are not sure if this study indicates a greater / lesser / same chance of this?

If an anthropogenic thermal anomaly this century will eventually (and inexorably) propogate to and destabalize significant amounts of methane hydrates in future centuries — shouldn't this be a consideration for policy makers?

HR made a comment in # 22 «But if they've (Shakhova & Semiletov) agreed nobody has been able to show hydrates above the stability zone, no shallow, metastable hypothetical hydrates found — that should revise the expected methane bomb down to 1 / 50th — 2 percent — of the claimed size.»

Generally, there are indications that if we reach 4 to 6C rise there is a chance possibly for larger methane hydrate release once the oceans warm up.

SkS: In your JGR paper from 2010 you state that methane hydrate in Siberia can occur at depths as shallow as 20 m. Have any such remarkably shallow methane hydrate deposits on the ESAS been directly observed / sampled and if so, how could methane hydrate have formed at such depths?

So if I move way north expecting the weather to warm Wind and natural gas from methane hydrates could be captured more easily Than distant solar radiation.

Even if most of this will probably not escape in any eventuality, I think it's very important to determine as soon as possible whether we're talking about one well with a bad cement job, one well with methane hydrate melting around it, failure of containment of most wells in Bovanenkovo (which after all will all have much the same conditions at the top of the reservoir), or failure of containment of most wells in the Yamal Project.

And finally, what about Mark's questions (# 3) and other factors not discussed here — do all these effects re Arctic ice lead scientists to believe there is a greater and / or earlier chance (assuming we continue increasing our GHG emissions — business as usual) of melting hydrates and permafrost releasing vast stores of methane into the atmosphere than scientists believed before the study, or is the assessment of this about the same, or scientists are not sure if this study indicates a greater / lesser / same chance of this?

If I understand correctly, most of the top of the methane hydrate level is right at the edge of destabilization.

-- and if at some time in the future there is a major adjustment to GCMs modelling like plugging in a new science based assumption that x warming will actually / or has triggered negative feedbacks like ASI area / piomass loss, or methane hydrates emissions inott eh atmosphere versus the present GCMs that such changes in the GCMs be noted in these Summary Key data Updates.

What is concerning is the possibility that rapid global warming could occur faster than many people believe is possible, if global warming due to atmospheric carbon dioxide causes the Earth's atmosphere to warm enough to release enormous deposits of frozen methane (CH4) that are stored in the permafrost above the Arctic Circle and in frozen methane ice, known as methane hydrate, underneath the floors of the oceans throughout the world (see: How Methane Gas Releases Due To Global Warming Could Cause Human Extinmethane (CH4) that are stored in the permafrost above the Arctic Circle and in frozen methane ice, known as methane hydrate, underneath the floors of the oceans throughout the world (see: How Methane Gas Releases Due To Global Warming Could Cause Human Extinmethane ice, known as methane hydrate, underneath the floors of the oceans throughout the world (see: How Methane Gas Releases Due To Global Warming Could Cause Human Extinmethane hydrate, underneath the floors of the oceans throughout the world (see: How Methane Gas Releases Due To Global Warming Could Cause Human ExtinMethane Gas Releases Due To Global Warming Could Cause Human Extinction).

Even if the estimates of the ice sheet collapsing by the end of the century were correct, however, it would likely take much longer than that for the effect of methane hydrates to become detectable in the atmosphere, says Alexey Portnov, a researcher at the Arctic University of Tromsø in Norway.

In addition, if permafrost melts, releasing its long - held carbon dioxide or methane into the atmosphere, and methane hydrates at the bottom of the continental shelves of the Arctic Ocean are destabilized, there could be highly accelerated warming.

We might get a short cycle of a few thousand years, or we might a hugely extended cycle of atmospheric scrubbing, tens of thousands of years, if the methane in the hydrates boils off to be later captured by the algae and resequestered as oil.

Moreover, as if discovering methane emissions from the deep seas of the Arctic isn't already of major concern, a recent study discovered immense amounts of methane locked under Antarctic ice: «They... calculated that the potential amount of methane hydrate and free methane gas beneath the Antarctic Ice Sheet could be up to 4 billion metric tons, a similar order of magnitude to some estimates made for Arctic permafrost.

However, if the temperature warms, or the pressure is reduced (for instance if local sea level decreases), the hydrate will break up and release the methane as gas which can bubble up through the ocean and enter the atmosphere.

Methane hydrates — methane molecules trapped in frozen water molecule cages in tundra and on continental shelves — and organic matter such as peat locked in frozen soils (permafrost) are likely mechanisms in the past hyperthermals, and they provide another climate feedback with the potential to amplify global warming if large scale thawing occurs [209]-Methane hydrates — methane molecules trapped in frozen water molecule cages in tundra and on continental shelves — and organic matter such as peat locked in frozen soils (permafrost) are likely mechanisms in the past hyperthermals, and they provide another climate feedback with the potential to amplify global warming if large scale thawing occurs [209]-methane molecules trapped in frozen water molecule cages in tundra and on continental shelves — and organic matter such as peat locked in frozen soils (permafrost) are likely mechanisms in the past hyperthermals, and they provide another climate feedback with the potential to amplify global warming if large scale thawing occurs [209]--[210].

If the ice sheets retreat the weight of the ice will be lifted from the ocean floor, the gas hydrates will be destabilised and the methane will be released.

Because the world faces a fossil fuel glut in the future — the torrents of new shale oil and gas that increasingly flood world markets could themselves be swamped by next - generation methane hydrate fuels — Canada's energy resources could depreciate if left to stagnate in the ground.

The Minerals Management Service estimates that the Gulf may hold 6,700 tcf of methane hydrate in sand — enough to satisfy U.S. natural gas demand for about 290 years, if all of it could be removed economically.

Methane is a greenhouse gas 20 times more potent than carbon dioxide, and it is thought that some gas hydrate deposits could become unstable if disturbed.

Given that there is as much Methane Hydrate than all the other fossil energies all together if we start to tap into this we will be cooked.

If you're wondering whether carbon dioxide hydrates could be as treacherous as methane hydrates, I should pass on Stott's warning that the mechanisms involved are different.

Methane hydrates, if they gasified, would leave a big CH4 peak in the ice cores.

I wonder if this methane came from the methane clathrates (hydrates)?

If there is a regional layer of high salt methane hydrate, shallow, at 70 - 150 meters and so susceptible to global warming, and if that layer is going to start to blow, then drilling to relieve pressure seems like a good idea, to mIf there is a regional layer of high salt methane hydrate, shallow, at 70 - 150 meters and so susceptible to global warming, and if that layer is going to start to blow, then drilling to relieve pressure seems like a good idea, to mif that layer is going to start to blow, then drilling to relieve pressure seems like a good idea, to me.

If there is a shallow layer of high salt terrestrial methane hydrate that causes gas blowouts, encountered at multiple gas fields in Siberia, that is a previously uncounted phenomenon.

If there is a regional layer of Siberian methane hydrate at about 100 meters, total methane content of that layer could be on the order of a gigaton or two of methane, as a worst case, I think.

And note their Section 4 — contemplating what happens if deep warm water currents change in a way that changes the current temperature in areas where methane hydrates are in equilibrium, suggesting the possibility of a rapid large scale release of methane gas.

If lots of methane hydrates are melting, wouldn't we expect a cooling, since that change - of - state reaction is endothermic?

Correct me if I'm wrong, but I believe the destabilization depth for methane in near 0 degree C temps is 200 meters, so the statement that I have seen here and elsewhere that the methane hydrate is at that depth should not surprise us and should not lead us to think that it is therefore stable — it is right on the edge of destabilizing, any even slight amount of warming will do so.

RealClimate is wonderful, and an excellent source of reliable information.As I've said before, methane is an extremely dangerous component to global warming.Comment # 20 is correct.There is a sharp melting point to frozen methane.A huge increase in the release of methane could happen within the next 50 years.At what point in the Earth's temperature rise and the rise of co2 would a huge methane melt occur?No one has answered that definitive issue.If I ask you all at what point would huge amounts of extra methane start melting, i.e at what temperature rise of the ocean near the Artic methane ice deposits would the methane melt, or at what point in the rise of co2 concentrations in the atmosphere would the methane melt, I believe that no one could currently tell me the actual answer as to where the sharp melting point exists.Of course, once that tipping point has been reached, and billions of tons of methane outgass from what had been locked stores of methane, locked away for an eternity, it is exactly the same as the burning of stored fossil fuels which have been stored for an eternity as well.And even though methane does not have as long a life as co2, while it is around in the air it can cause other tipping points, i.e. permafrost melting, to arrive much sooner.I will reiterate what I've said before on this and other sites.Methane is a hugely underreported, underestimated risk.How about RealClimate attempts to model exactly what would happen to other tipping points, such as the melting permafrost, if indeed a huge increase in the melting of the methal hydrate ice WERE to occur within the next 50 years.My amateur guess is that the huge, albeit temporary, increase in methane over even three or four decades might push other relevent tipping points to arrive much, much, sooner than they normally would, thereby vastly incresing negative feedback mechanisms.We KNOW that quick, huge, changes occured in the Earth's climate in the past.See other relevent posts in the past from Realclimate.Climate often does not change slowly, but undergoes huge, quick, changes periodically, due to negative feedbacks accumulating, and tipping the climate to a quick change.Why should the danger from huge potential methane releases be vievwed with any less trepidation?

Assuming 1 % hydrate by pore water volume were released on average from the slide volume, you get a methane release of about 0.8 Gton of C. Even if all of the hydrate made it to the atmosphere, it would have had a smaller climate impact than a volcanic eruption (I calculated the methane impact on the radiative budget here).

It's not clear boreal feedbacks are even necessary to lighting off tropical biomass (fire once again), but they'll certainly speed the process way up; if that does happen in turn we're on our way to a hyperthermal (with some lag since the oceans have to warm enough to trigger a self - sustaining loss of shallow methane hydrates).

Question # 2: If the planet is cooling, why would formerly frozen methane hydrate deposits be thawing and releasing all over the globe?