Sentences with phrase «methane hydrates at»

Xiaoli Liu and Dr. Peter Flemmings have studied high salt methane hydrates at Hydrate Ridge, off the Oregon coast.

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.

Furthermore, seismic activity has been proven to locally destabilize subsea methane hydrates at many sites around the world.

When I read it I had in mind the frozen methane hydrates at the bottom of the ocean (from «biologic processes»).

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 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.

Not exact matches

The race is on to tap the world's biggest and most unusual fossil fuel supply — methane trapped in frozen hydrates in permafrost and at the bottom of the ocean

Gas hydrates, icelike deposits of methane locked away in permafrost and buried at the ocean bottom, may pose a threat to our climate (see Discover, March 2004).

While a cataclysmic event among the methane hydrate mounds could unfold sometime in the future, violent eruptions are the norm at Endeavour Ridge, the site of another NEPTUNE research node.

This created massive craters that are still actively seeping methane» says Karin Andreassen, first author of the study and professor at CAGE Centre for Arctic Gas Hydrate, Environment and Climate.

The key ingredient is gas hydrate, a substance that forms when hydrocarbon gases like methane and ethane come into contact with water at the right temperature and pressure.

Methane hydrates were later found in permafrost in the 1960s, and in the oceans, commonly on the edges of the continental shelves, but only at certain ocean pressures and temperatures.

It used to be thought that the methane in hydrates was made the way oil is — that Earth's internal heat makes methane, the smallest hydrocarbon, by cracking bigger hydrocarbons at depths of more than a mile below the seafloor.

There is a precise curve of temperatures and pressures that define the depth at which methane hydrates exist.

At a lower pressure — approximately 4 GPa — methane and molecular hydrogen interact, forming co-crystals (where two molecules together create one crystal structure), and at 6 GPa, hydrates — CO-crystals made of methane and water — are formeAt a lower pressure — approximately 4 GPa — methane and molecular hydrogen interact, forming co-crystals (where two molecules together create one crystal structure), and at 6 GPa, hydrates — CO-crystals made of methane and water — are formeat 6 GPa, hydrates — CO-crystals made of methane and water — are formed.

At the December AGU meeting, Robert Collier of Oregon State University presented a glimpse of the methane concentrations in the water above Hydrate Ridge.

Natural methane hydrates were first discovered by Russian scientists in the late 1960s in Siberian permafrost — where the ground is so cold that hydrates can form at shallower depths and at lower pressures than under the sea — and then, in the 1970s, at the bottom of the Black Sea.

Huge quantities of methane, the theories say, have escaped from seafloor hydrates at various times in the past, wreaking havoc.

The probe from DeLong and Hinrichs, on the other hand, had worked right away: The Hydrate Ridge sediments were loaded with their methane eater, which is not a bacterium at all but a species of Archaea, an ancient group of microbes that diverged from bacteria billions of years ago and are as distinct from them now, genetically speaking, as humans are.

Previous work has estimated that more than a trillion tonnes of methane lie under the shelf, trapped inside lattices of ice known as hydrates, at depths as shallow as 20 metres.

Exponentially less methane would be able to reach the atmosphere in waters that are thousands of feet deep at the very edge of the shallow seas near continents, which is the area of the ocean where the bulk of methane hydrates are,» Sparrow says.

Gas hydrates — a mixture of ice and methane — are found only under high pressure and at cold temperatures, and they are expected to make up a significant portion of the energy mix once existing oil fields dwindle, says David Scott, manager of the Northern Resources Development Program for Natural Resources Canada.

Methane hydrates, also known as «burning ice», occur at all ocean margins.

The methane hydrates with the highest climate susceptibility are in upper continental margin slopes, like those that ring the Arctic Ocean, representing about 3.5 percent of the global methane hydrate inventory, says Carolyn Ruppel, a scientist who leads the Gas Hydrates Project at thydrates with the highest climate susceptibility are in upper continental margin slopes, like those that ring the Arctic Ocean, representing about 3.5 percent of the global methane hydrate inventory, says Carolyn Ruppel, a scientist who leads the Gas Hydrates Project at tHydrates Project at the USGS.

Most methane hydrates are buried in ocean water so deep that the journey through the water column is too far for the gas to ever reach the atmosphere, according to Ed Dlugokencky, a researcher at the National Oceanic and Atmospheric Administration.

Even where methane increases are observed at the ocean surface, scientists need better data to determine whether emissions come from hydrates or other seafloor sources.

Research in 2008 led by oceanographer Natalia Shakhova, now at the University of Alaska Fairbanks, estimated the thawing shelf could release a 50 - gigaton pulse of methane from hydrates over 10 years — about 8 percent of the methane stored in the shelf's sediments.

But judging by today's stores of methane hydrates, there doesn't seem to have been enough methane stored at the time of the PETM to drive that much warming.

Umbertoluca Ranieri, PhD student at ILL and EPFL, and lead author of this study says: «These results are important in improving our understanding of many fundamental non-equilibrium phenomena involving methane clathrate hydrates; for example, the replacement kinetics during gas exchange in case of conversion between the clathrate structures I and II.

My research indicates that the Siberian peat moss, Arctic tundra, and methal hydrates (frozen methane at the bottom of the ocean) all have an excellent chance of melting and releasing their stored co2.Recent methane concentration figures also hit the news last week, and methane has increased after a long time being steady.The forests of north america are drying out and are very susceptible to massive insect infestations and wildfires, and the massive die offs - 25 % of total forests, have begun.And, the most recent stories on the Amazon forecast that with the change in rainfall patterns one third of the Amazon will dry and turn to grassland, thereby creating a domino cascade effect for the rest of the Amazon.With co2 levels risng faster now that the oceans have reached carrying capacity, the oceans having become also more acidic, and the looming threat of a North Atlanic current shutdown (note the recent terrible news on salinity upwelling levels off Greenland,) and the change in cold water upwellings, leading to far less biomass for the fish to feed upon, all lead to the conclusion we may not have to worry about NASA completing its inventory of near earth objects greater than 140 meters across by 2026 (Recent Benjamin Dean astronomy lecture here in San Francisco).

Methane hydrates are formed by bonding with water to make an ice - like substance in certain temperature / pressure conditions that can be found at shallow water depths in

I have posted on RealClimate about 4 times in the past 5 years regarding the potential thaw of the methal hydrate deposits at the bottom of the oceans.I stated in my posts on your website that I believe firmly that those deposits are in quite a good bit of danger of melting from climate change feedback mechanisms.On Nov 8th, ScienceDaily posted a huge new study on the PETM boundary 55 million years ago, and some key data on how the methane at that point may very well have melted and contributed to the massive climate shift.I am an amateur who reads in the new a lot about climate change.I'd now like to say «I told you so!!!»

At 0 degrees C, you need a pressure equivalent to ~ 250 meters of water depth to get enough dissolved methane for hydrate to form.

In at least one instance, the inferred pore space gas hydrate occurred at 119m, a depth shallower than the predicted methane hydrate stability zone.

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?

Consider just how much commercial cred fracked gas & oil had 10 yrs ago, and then look at the current worldwide research efforts both on methane hydrates» extraction and also on coal - seam gasification.

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.

Of course, it is precisely one of those exceptions that is most concerning to some of us, and Archer himself noted that, «The Siberian margin is one example of a place where methane hydrate is melting today, presumably at an accelerated rate in response to anthropogenic warming.

It can also melt vast quantities of methane hydrates frozen into tundra, and also at depths along the oceanic continental shelves.

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.

The rising sea level increases pressure at certain depths, which expands the area of methane hydrate stability.

Model studies at the Moscow State University Geology Department show something quite to the contrary: methane hydrates respond to climate changes 20,000 to 40,000 years after the fact.

Methane hydrate forms in cold temperatures and under high pressure — conditions that can be found at the bottom of the ocean.

First, given that Arctic seabeds are now releasing methane from gas hydrates at present levels of global warming, the 2 ° limit and carbon budget that Paul refers to is simply irrelevant.

But researchers such as Natalia Shakhova — a visiting scientist at the University of Alaska in Fairbanks and a participant in some of the Siberian Shelf scientific cruises — are concerned that the undersea permafrost layer has become unstable and is leaking methane long locked in ice crystals, known as methane hydrates.

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.

Portnov studies the remnants of methane hydrates exposed at the end of the last ice age in the Arctic, as well as methane hydrates currently thawing out of Arctic permafrost today.

At the riskier, «far out» end, does it include methane hydrates?

Off the Washington and Oregon coast, 168 bubble plumes had been detected in the past 10 years, a disproportionate number of which were found at a critical depth for methane hydrates» stability.