Good Gas, Bad Gas By Marianne Lavelle National Geographic; December, 2012
Burn natural gas and it warms your house. But let it leak, from fracked wells or the melting Arctic, and it warms the whole planet.
The last rays of sun filter through the snow-covered spruces along the shore of Goldstream Lake, just outside Fairbanks, Alaska. Out on the lake Katey Walter Anthony stares at the black ice beneath her feet and at the white bubbles trapped inside it. Large and small, in layer upon layer, they spread out in every direction, like stars in the night sky. Walter Anthony, an ecologist at the University of Alaska Fairbanks, grabs a heavy ice pick and wraps the rope handle around her wrist. A graduate student holds a lighted match above a large bubble; Walter Anthony plunges the pick into it.
Gas rushing from the hole ignites with a whoomp that staggers her. “My job’s the worst, because usually you catch on fire,” she says, smiling. In the gathering twilight she and her team ignite one bubble after another.
The flames confirm that the bubbles are methane, the main component of natural gas. By counting and measuring them, Walter Anthony is trying to gauge how much methane is rising from Goldstream Lake—and from the millions of similar lakes that now occupy nearly a third of the Arctic region. The Arctic has warmed much faster than the rest of the planet in recent decades, and as the permafrost has melted, old lakes have grown and new ones have formed. Methane bubbles from their muddy depths in a way that is hard to quantify—until the first clear ice of fall captures a snapshot of the emissions from an entire lake.
Sometimes as Walter Anthony walks that ice, in Alaska, Greenland, or Siberia, a stamp of her boot is enough to release an audible sigh. Some lakes, she says, have “hot spots” where the methane bubbling is so strong that ice never forms, leaving open holes big enough to spot from an airplane. “It could be 10 or 30 liters of methane per day from one little hole, and it does that all year,” she says. “And then you realize there are hundreds of spots like that and millions of lakes.” By venting methane into the atmosphere, the lakes are amplifying the global warming that created them: Methane is a potent greenhouse gas. Carbon dioxide is the main one, because the atmosphere holds 200 times as much of it. But a given amount of methane traps at least 25 times as much heat—unless you burn it first. Then it enters the atmosphere as CO₂.
That’s the other side of this Jekyll-and-Hyde story: A lot of methane is being burned these days. In the past decade the technology called hydraulic fracturing, “fracking” for short, has enabled drillers in the United States to extract natural gas from deeply buried shales they couldn’t tap before. Natural gas supplies have surged; prices have plummeted. Fracking is now spreading around the world, and it’s controversial. The gas boom has degraded landscapes and polluted water. But it has also had environmental benefits. Natural gas burns much cleaner than coal. In part because American power plants have been switching from coal to cheap gas, U.S. emissions of CO₂ from fossil fuels fell last year, even as the world set another record.
The catch is, methane emissions are rising. What’s coming out of Arctic lakes is troubling, Walter Anthony says, because some of it seems to be coming not from bottom mud but from deeper geologic reservoirs that had hitherto been securely capped by permafrost—and that contain hundreds of times more methane than is in the atmosphere now. Still, most methane emissions today come from lower latitudes, and most are related more directly to human activities. A growing amount seems to be leaking, for instance, from gas wells and pipelines. Just how warm Earth gets this century will hinge in part on how we balance the good and bad of methane—on how much of it we capture and burn, and how much we inadvertently let loose.
Methane is the simplest hydrocarbon—a single carbon atom surrounded by four hydrogen atoms. It usually forms when larger organic molecules are broken down, either by microbes or by heat. The microbes produce it when they eat dead plant matter in wet, oxygen-poor environments. They’re the source of the methane bubbling up from Goldstream Lake; from swamps and marshes all over; from human-made rice fields, landfills, and manure lagoons; and from the stomachs of cows and other ruminants. Termites emit a lot of methane too.
Most of the natural gas we tap for fuel, however, was formed not by microbes but by heat and pressure deep underground—as oil and coal were, and often in the same places. In coal mines methane is an explosion hazard; in oil fields it was long considered a nuisance to be burned off or, worse, vented directly into the atmosphere. Liquid oil was more valuable as fuel and much easier to transport to markets. Then pipelines built during the post–World War II construction boom made gas more transportable. The energy industry began to exploit massive natural gas reservoirs in places like Russia, Qatar, and Iran.
The United States produces the bulk of its own gas, but U.S. production peaked in 1973. By 2005 the country seemed to be running short, and the industry was building expensive new tanker terminals to import liquefied natural gas. The fracking boom changed that. Since 2005 gas production from deep shales has increased more than tenfold; it now accounts for more than a third of total production, which last year surpassed the 1973 record. Within a decade, according to a Department of Energy (DOE) forecast, the U.S. will become a net exporter of gas.
Estimates of how much gas is locked up in shales and how long the boom can last have varied widely. In 2011 DOE put the amount of “unproved resources” of shale gas at 827 trillion cubic feet; in 2012 it cut that estimate by more than 40 percent. Production from fracked wells has declined faster than DOE analysts had expected. So some critics believe the boom is a bubble that will soon burst. But DOE still projects that U.S. gas production will rise rapidly and that shale gas will make up half the total by 2035.
And deep shales are not the last methane source. DOE and the industry are trying to figure out how to tap the largest one of all—the methane hydrates that lie frozen under vast areas of seafloor and Arctic permafrost. Worldwide, hydrates may contain more energy than all other fossil fuels combined. They’re usually snow-white and look like ice, but they’re strange stuff, and extracting the methane is tricky. Each molecule is trapped in a cage of water molecules that’s stable only at high pressure and low temperatures; change either just a bit, and the cage crumbles. The escaping methane balloons in volume by a factor of 164.
Oil companies working on continental margins have to take care that extracting oil through an overlying hydrate layer does not disrupt it and perhaps damage the well. Climate scientists worry that global warming could destabilize hydrate layers, on land or at sea, triggering a massive methane release that would amplify the warming. A few scientists take seriously a catastrophic scenario in which the release happens rapidly, within a human lifetime, and the planet’s temperature spikes.
The atmospheric methane concentration has risen nearly 160 percent since preindustrial times, to 1.8 parts per million. For a few years, from 1999 to about 2006, it seemed to level off. Some researchers credit Asian rice farmers, who began draining their paddies during the growing season to conserve water—which reduced methane emissions as well. Another theory credits the oil industry, which started capturing and selling methane it used to simply vent. Since 2006, though, atmospheric methane has been rising again. Many observers believe it’s no coincidence that the number of wells punched into deep shales has been soaring too.
Relief in Every Window, but Global Worry Too
by Elizabeth Rosenthal and Andrew W. Lehren, New York Times; June 20, 2012
In the ramshackle apartment blocks and sooty concrete homes that line the dusty roads of urban India, there is a new status symbol on proud display. An air-conditioner has become a sign of middle-class status in developing nations, a must-have dowry item.
It is cheaper than a car, and arguably more life-changing in steamy regions, where cooling can make it easier for a child to study or a worker to sleep.
But as air-conditioners sprout from windows and storefronts across the world, scientists are becoming increasingly alarmed about the impact of the gases on which they run. All are potent agents of global warming.
Air-conditioning sales are growing 20 percent a year in China and India, as middle classes grow, units become more affordable and temperatures rise with climate change. The potential cooling demands of upwardly mobile Mumbai, India, alone have been estimated to be a quarter of those of the United States.
Air-conditioning gases are regulated primarily though a 1987 treaty called the Montreal Protocol, created to protect the ozone layer. It has reduced damage to that vital shield, which blocks cancer-causing ultraviolet rays, by mandating the use of progressively more benign gases. The oldest CFC coolants, which are highly damaging to the ozone layer, have been largely eliminated from use; and the newest ones, used widely in industrialized nations, have little or no effect on it.
But these gases have an impact the ozone treaty largely ignores. Pound for pound, they contribute to global warming thousands of times more than does carbon dioxide, the standard greenhouse gas.
The leading scientists in the field have just calculated that if all the equipment entering the world market uses the newest gases currently employed in air-conditioners, up to 27 percent of all global warming will be attributable to those gases by 2050.
So the therapy to cure one global environmental disaster is now seeding another. “There is precious little time to do something, to act,” said Stephen O. Andersen, the co-chairman of the treaty’s technical and economic advisory panel.
The numbers are all moving in the wrong direction.
Atmospheric concentrations of the gases that replaced CFCs, known as HCFCs, which are mildly damaging to the ozone, are still rising rapidly at a time when many scientists anticipated they should have been falling as the treaty is phasing them out. The levels of these gases, the mainstay of booming air-conditioning sectors in the developing world, have more than doubled in the past two decades to record highs, according to the National Oceanic and Atmospheric Administration.
And concentrations of the newer, ozone-friendly gases are also rising meteorically, because industrialized countries began switching to them a decade ago. New room air-conditioners in the United States now use an HFC coolant called 410a, labeled “environmentally friendly” because it spares the ozone. But its warming effect is 2,100 times that of carbon dioxide. And the treaty cannot control the rise of these coolants because it regulates only ozone-depleting gases.
The treaty timetable requires dozens of developing countries, including China and India, to also begin switching next year from HCFCs to gases with less impact on the ozone. But the United States and other wealthy nations are prodding them to choose ones that do not warm the planet. This week in Rio de Janeiro, Secretary of State Hillary Rodham Clinton is attending the United Nations Conference on Sustainable Development, also known as Rio+20, where proposals to gradually eliminate HFCs for their warming effect are on the provisional agenda.
But she faces resistance because the United States is essentially telling the other nations to do what it has not: to leapfrog this generation of coolants. The trouble is, there are currently no readily available commercial ozone-friendly alternatives for air-conditioners that do not also have a strong warming effect — though there are many on the horizon.
Nearly all chemical and air-conditioning companies — including DuPont, the American chemical giant, and Daikin, one of Japan’s leading appliance manufacturers — have developed air-conditioning appliances and gases that do not contribute to global warming. Companies have even erected factories to produce them.
But these products require regulatory approvals before they can be sold, and the development of new safety standards, because the gases in them are often flammable or toxic. And with profits booming from current cooling systems and no effective regulation of HFCs, there is little incentive for countries or companies to move the new designs to market.
“There are no good solutions right now — that’s why countries are grappling, tapping in the dark,” said RajendraShende, the recently retired head of the Paris-based United Nations ozone program, who now runs the Terre Policy Center in Pune, India.
An Unanticipated Problem
The 25-year-old Montreal Protocol is widely regarded as the most successful environmental treaty ever, essentially eliminating the use of CFC coolants, which are highly damaging to the ozone layer. Under its terms, wealthier countries shift away from each harmful gas first, and developing countries follow a decade or more later so that replacement technologies can be perfected and fall in price.
Concentrations of CFC-12, which had been growing rapidly since the 1960s, have tapered off since 2003, thanks to the treaty’s strict phaseout schedule. In 2006, NASA scientists concluded that the ozone layer was on the mend.
But that sense of victory has been eclipsed by the potentially disastrous growth in emissions from the newer air-conditioning gases. While a healthier ozone layer itself leads to some warming, far more warming results from the tendency of these coolant gases to reflect back heat radiating off the Earth.
When the treaty set its rules in the mid-1980s, global warming was poorly understood, the cooling industry was anchored in the West, and demand for cooling was minuscule in developing nations.
That has clearly changed. Jayshree Punjabi, a 40-year-old from Surat, was shopping for an air-conditioner at Vijay Sales in Mumbai on a recent afternoon. She bought her first one 10 years ago and now has three. “Now almost every home in Surat has more than one,” she said. “The children see them on television and demand them.”
Refrigeration is also essential for these countries’ shifting food supplies. “When I was a kid in Delhi, veggies came from vendors on the street; now they all come from the supermarket,” said AtulBagai, an Indian citizen who is the United Nations ozone program’s coordinator for South Asia.
In 2011, 55 percent of new air-conditioning units were sold in the Asia Pacific region, and the industry’s production has moved there. Last year, China built more than 70 percent of the world’s household air-conditioners, for domestic use and export. The most common coolant gas is HCFC-22. In 2010, China produced about seven times the amount of that gas as the United States.
With inexpensive HCFC-22 from Asia flooding the market, efforts to curb or eliminate its use have been undercut, even in the United States. For example, although American law now forbids the sale of new air-conditioners containing HCFC, stores have started selling empty components that can be filled with the cheap gas after installation, enabling its continued use.
An Alert on Ocean Acidity
By John Collins Rudolf, New York Times; December 8, 2010
Carbon dioxide emissions from man-made sources are causing the acidity level of the world's oceans to rise at what is probably the fastest rate in 65 million years, threatening global fisheries that serve as an essential food source for billions of people, according to a new United Nations report.
Roughly 25 percent of the carbon dioxide generated by the combustion of fossil fuels enters the oceans, and as the gas dissolves in seawater it changes into carbonic acid. One result has been a rapid alteration in ocean chemistry that is already affecting marine organisms.
The acidity of the oceans has grown 30 percent since the beginning of the Industrial Revolution. At current emission rates, ocean acidity could be 150 percent higher by the end of the century, the report states.
Marine life and coral reefs have already shown vulnerability to rising levels of acidity, and the changes expected in coming decades are severe enough that they could have a serious impact on the ability of people around the world to harvest needed protein from the seas, according to Carol Turley, senior scientist at Britain's National Oceanography Center and the lead author of the report.