If the rest of the process pans out, the island nation could eventually overcome its lack of home-grown deposits of fossil fuels and start burning the stuff as prodigiously as other nations do their own carbon-based resources. Currently, extraction of this exotic fuel is far more expensive than other means of obtaining natural gas, hydraulic fracking being one example. Both Japan and the United States have been actively investigating the potential of methane hydrates since 1999. Hiroko Tabuchi at The New York Times reports:
Experts estimate that the carbon found in gas hydrates worldwide totals at least twice the amount of carbon in all of the earth’s other fossil fuels, making it a potential game-changer for energy-poor countries like Japan. Researchers had previously successfully extracted gas from on-shore methane hydrate reservoirs, but not from beneath the seabed, where much of the world’s deposits are thought to lie.Even with the acknowledgement of these vast amounts of carbon, it takes until paragraph 22, the last in the story, before we get this caveat:
Scientists at the U.S.G.S. note, however, that there is still a limited understanding of how drilling for hydrates might affect the environment, particularly the possible release of methane, a greenhouse gas, into the atmosphere, and are calling for continued research and monitoring.Methane hydrates, often called—"methane ice" or "fire ice"—comprise crystalline structures of gas molecules surrounded by an icy "cage" of water molecules found beneath the Arctic permafrost and the seabed throughout the world. It may look like an ice cube, but put a match to it and it burns.
Released into the air, methane is 15 to 20 times more effective at trapping heat than another greenhouse gas, carbon dioxide, but doesn't remain in the atmosphere as long. When it is burned, methane emits 40 percent less carbon dioxide than burning coal and 30 percent less than oil. And unlike coal, it contains lesser amounts of environmentally damaging nitrogen and sulfur oxides. Each cubic foot of methane ice releases 164 cubic feet of gas. Estimates of the worldwide amount of gas in methane ice vary wildly, but the highest puts it at 700,000 trillion cubic feet. Please continue reading about methane hydrates below the fold.
Today it is assumed that in the worst case, with a steady warming of the ocean of 3 degrees Celsius, around 85 per cent of the methane trapped in the sea floor could be released into the water column.Then, too, widespread mining of the seabed for methane ice could lead, some researchers and environmental advocates worry, to collapses in the ocean floor that, even without higher temperatures, would release large quantities of methane gas to the ocean's surface and thus the atmosphere.
Other, more sensitive models predict that methane hydrates at great water depths are not threatened by warming. According to these models, only the methane hydrates that are located directly at the boundaries of the stability zones would be primarily affected. At these locations, a temperature increase of only 1 degree Celsius would be sufficient to release large amounts of methane from the hydrates. The methane hydrates in the open ocean at around 500 metres of water depth, and deposits in the shallow regions of the Arctic would mainly be affected.
The impact of burning the stuff in large quantities is another matter.
The U.S. Geological Service has studied methane hydrates for more than a decade, but researchers readily concede that they do not yet have a full understanding of them or the impact they could have on climate change.
Natural gas obtained by standard drilling techniques and by hydraulic fracking is being increasingly used in place of coal because it is cheaper, pollutes less and has a smaller carbon footprint. It is viewed as a bridge fuel by many energy experts, including Ernest Moniz, the MIT scientist that President Obama has nominated to be the next secretary of the Department of Energy.
But if the hydrates become economically accessible, the question becomes whether use of the natural gas separated from them will be a bridge or a twelve-lane highway stretching far into the future. Using fuels that produce fewer greenhouse gas emissions is a good thing. But the overburdened atmosphere needs more than a mere reduction.