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Two things going up in the world today: gas prices and average air
temperatures. And the one thing that connects them both? Frozen natural
gas under the seafloor. That's considered a depth shallower than
expected, mind you.
To be more accurate, the frozen natural gas
is called natural gas hydrates. They form when a gas stream is cooled
below its hydrate formation temperature - a.k.a. the dew point of
natural gas - in the presence of water. Gas turns to liquid droplets at
a temperature lower than water freezes: the results are "dirty ice"
containing trapped natural gas.
This
thing can occur a lot in gas pipelines if people aren't careful. Ice in
gas pipes are like ice in water pipes: not a pretty sight when they
occur, not a pretty sight when disasters
occur because of them (and natural gas is decidedly a lot more
dangerous than water). But we're not concerned about those deposits
here. Hydrates occur in the wild too (usually as methane clathrate or
"methane ice") in conditions of high gas pressure and low temperature.
Scientists normally would expect them to form underground, usually
below the seabed, and in what's known as the Gas Hydrate Stability
Zone, where the conditions for gas to ice up can be found. Below this,
the gas remains dissolved in water; above the GHSZ, they fizz like
opened soda pop and escape the water into the atmosphere.
Until a scientific expedition supported by the Integrated Ocean Drilling Program (IODP) went off, dug relatively shallow holes in the waters off British Columbia, and found high concentrations of gas hydrates. “We found anomalous occurrences of high concentrations of gas hydrate
at relatively shallow depths, 50-120 meters below the seafloor,” says expedition co-chief Michael Riedel (McGill Univ., Montreal). Adds fellow co-chief Timothy S. Collett of the US Geological Survey, “What we’ve found will fundamentally change how we investigate the
impact of gas hydrate deposits.”
The findings strengthen hypotheses that gas hydrates can form in significant concentrations outside of the predicted GHSZ. Expedition 311 members speculate that sediments - like sand - can have a positive effect on the formation of hydrates. Their core drilling samples were extracted from sand-rich sediment layers beneath the seabed. 
So what's all this ice cubes of explosive gas and drilling of holes in the waters off western Canada have to do with skyrocketing pump prices and increasingly unbearable summers? Potential bad news and potential good news.
The potential bad news is that the methane in methane ice is a very powerful greenhouse gas. Remember what we said about the methane fizzing from the ice like soda pop? Scientists theorize that increasing sea temperatures will make all this gas soda popping a lot more common. Come to think of it, it's kind of like a vicious cycle, isn't it? Waters warm, methane escapes, water eventually gets more warm, more gas eventually escapes.
Worse yet, scientists also speculate that a massive release of methane from hydrates, and the resulting global warming, caused one of the hottest periods in Earth's history, known as the Paleocene-Eocene Thermal Maximum. They also think it may be a possible reason (or one of the reasons) for what's known as the Permian-Triassic extinction, also known as the "Great Dying." That can't be good.
On a more positive note, the potential good news is that methane ice can one day become a fuel source. Researchers and car manufacturers are looking to methane to provide hydrogen for fuel cell cencepts - like, say Honda. It's just rather hard to mine methane hydrates for the same reason that they are fizzing into the atmosphere: once they're brought into conditions of higher temperature or lower pressure outside of their formation zone, they fizz out of the water ice. Solve that problem of capturing the gas as it bubbles out - or keeping the hydrate intact throughout the extraction process - and make it economical, and those frozen blocks of gas may one day drive you from New York to Los Angeles. And if the only by-product of note from the car is water... well, that's some good news for a change.
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