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Fracking Yeas and Nays

Fracking, short for hydraulic fracturing, is a process which has been around for over 60 years but because of recent technological changes is being used to increase production of oil and gas. Basically a fluid is pumped underground under high pressure causing the substrate to fracture which allows oil and gas to move more readily through the fissures created into the well and up to the surface.

The historical precedent goes back to the post civil war era. Civil war veteran Col Roberts received a patent for a method to increase production in oil wells that involved dropping a nitroglycerin filled “torpedo” down the well shaft. The explosion would fracture the formation, increasing oil production.

Hydraulic fracturing began about 1950. The recent fracking boom is the result of a combination of advances to the technology including directional drilling and the use of “proppants” like sand and glass beads which prop open the fractures. The technique was pioneered here in the US but its use is rapidly expanding around the world.

There is no question that it is a hot button issue. Some claim that it is a useful, even necessary way to produce fuels for a growing economy. Others suggest the the environmental problems associated with the technique are so untoward as to require banning its use.

Natural gas, regardless of its source, has been called the Prince of Fuels. Among fossil fuels it is by far and away the cleanest burning. It has essentially none of the noxious impurities like sulfur and heavy metals that occur in both coal and oil. It also has a considerable advantage in that it produces more energy for the amount of carbon dioxide produced. Older coal fired power plants have been closing across the country, due in part to it replacement by natural gas plants. Natural gas could even replace liquid fuels for transportation as compressed natural gas (CNG) or by catalytic conversion to a liquid fuel.

Natural gas can be burned in turbines to generate electricity. Gas turbines are ideal as a source of rapidly dispatchable energy that combines well with intermittent renewable energy sources such as wind and solar panels. If the wind blows hard, you idle the turbines, light wind, power up just a few, no wind, turn ’em all on. Over half the natural gas produced in the US comes from fracking.

There are however serious downsides. Fracturing requires a toxic witches brew of hydraulic fluids and some suggest that these pollutants in the fluids have found their way into groundwater. Although it is not hard to imagine how this could happen, the evidence of it actually happening is scant. A more clearly defined problem is the cluster of shallow earthquakes that correlate well with spent fracking fluid reinjection sites. Once the fluid has been used it is disposed of by permanent injection into wells. This fluid under pressure lubricates the subterranean rock layers allowing them to move, hence earthquakes.

Natural gas, essentially methane, is itself a potent contributor to global warming. A final negative is the growing evidence that fugitive emissions from gas production and transmission facilities is a serious contributor to global warming.

These negatives are not insurmountable. Better well casing and location limitations can minimize the risk of ground water pollution. Reprocessing of used fluids, rather than injection will end the earthquake issue, and simply “tightening up” the production and transmission facilities will lessen the fugitive emissions.

Thawing Permafrost Feedback Loop

Within the scientific community there is no argument about global warming. It is real, and it is caused by human activities. Those activities include burning fossil fuels which release carbon dioxide (CO₂.) The carbon dioxide acts as a climatic blanket to retain heat in the atmosphere which would otherwise be radiated out to space.

Other activities which release carbon dioxide to the atmosphere are deforestation. Cutting trees causes the release of CO₂, if the biota is simply burned to clear land as is practiced in the rain forests of the Amazon and southeast Asia. Even if the timber is harvested for construction, there is still a significant portion of the biomass in the form of twigs, branches, roots, and shoots which degrade rapidly to release CO₂.

Carbon dioxide is only one of the so called greenhouse gasses, the major one, but only one just the same. Methane, CH4, is another greenhouse gas. On a per weight basis methane is much more effective at global warming than CO₂, but its contribution is lower as there is a lot less of it. That may be changing – read on.

As stated earlier, global warming is real, the planet is getting warmer and it is to a very large degree caused by humans. A question yet answered is how fast will the planetary temperature rise? That depends on how fast the concentrations of the gasses increase.

If there is one condition that keeps climate scientists up at night, it is a risk of a “runaway” feedback mechanism. If warming itself can cause the release of greenhouse gasses, then a feedback loop causes more heating which causes more gas release which causes more rapid heating which causes more rapid gas release…

Image from thepolicylass.org

Image from thepolicylass.org

Feedback loops exist, but how sensitive are they to what is happening now? A disturbing result was recently published in Nature Climate Change. One of the vagaries of climate change is that it is happening faster at the higher latitudes (nearer the poles) than near the equator. Not only are glaciers melting but areas of exposed permafrost are thawing rapidly. The permafrost is composed of a thick layer of accumulated biomass from the slow growth of moss, lichens, and sedge. There is estimated to be twice as much carbon sequestered in the permafrost as exists in the atmosphere.

The carbon in the permafrost can degrade in two ways depending on environmental conditions. Microbial action can convert the carbon to either CO₂ or methane. If more methane is produced the feedback loop is accelerated even faster than if CO₂ were produced.

This all starts with burning fossil fuels which enrich the atmosphere in carbon dioxide. This causes the climate to warm, which causes the permafrost to thaw which causes the production of even more carbon dioxide or even worse methane.

The only way to stem this cycle is to stop extracting and stop burning coal, oil, and methane. The Environmental Protection Agency has taken some early steps to limit burning coal, the worst of the fossil fuels.

sea ice

More Global Warming Denial

A London, England newspaper, the Daily Mail, recently ran a headline “ Myth of Arctic meltdown: Stunning satellite images show summer ice cap is thicker…than two years ago” This was rapidly picked up and shot around the blogosphere as a renunciation of the risk of Global Warming.

Arctic Sea Ice Minimum Coverage

Arctic Sea Ice Minimum Coverage

Really? REALLY? Based on two data points the paper decides that the work of literally thousands of scientists around the world is all wrong. No, no, no. The trend over the last 30 years of sea ice measurement show that the ice is thinning and the area of coverage is shrinking. Even the casual observer will notice that measurement of climatic variables is confounded by the fact of wide variations in both time and space in virtually all the variables – temperature, rainfall, seal level, etc.

We have warm years and cold years, but overall it is getting warmer when all the planet’s surface and air temperatures are averaged. Even though it has been a relatively cool (and wet) summer here in the central Arkansas, the warmest June in the history of recorded measurements happened in 2014. Given this is just one data point, but how about this: 9 of the 10 hottest Junes ever happened in the 21st century.

Another misleading claim is that global warming has stopped or at least slowed over the last few years. It is true that over the last few years it has not been getting hot as fast as previous years. The rate of heating has slowed somewhat, but only when you average surface and air temperatures as mentioned above.

The causative agent for global warming, the amount of heat trapping gasses in the atmosphere, are inexorably increasing, hence the a factor called radiative forcing is increasing. The real question is where is the missing heat. An article published recently in Science, the premier peer reviewed science journal published in the United States, has the answer.

It’s hiding in intermediate depths of the Atlantic and Southern Oceans. New data coupled with reanalysis of previously collected data show that a recurrent anomaly in salinity is the culprit. Changes in the saltiness of water affect its density, which can cause upwelling of the colder deeper water. When the colder water is brought to the surface it warms, absorbing heat.

Major ocean currents such as the Gulf Stream are driven by these kinds of differences in temperature and salinity. The Gulf Stream transports heat from Florida to Europe. Disrupt it and it could get hotter in Florida and colder in Europe.

Gulf Stream

Gulf Stream

In a related story, seeps of methane have been detected in the Atlantic ocean. Much methane lies near the continental shelf trapped in ice crystals known as clathrates. Warming of the water in the area of the clathrates could cause thawing which would release the methane.

The story gets even scarier when you consider that methane is a powerful heat trapping gas itself. Global warming is causing the release of methane which causes more global warming which causes more methane release – and around and around we go.