Global fossil fuel emissions of hydrocarbons are underestimated

Credit: Petr Kratochvil/Public Domain

Global levels of ethane and propane in the atmosphere have been underestimated by more than 50%, new research involving scientists at the University of York has revealed.

These hydrocarbons are particularly harmful in large cities where, through chemical reactions with emissions from cars, they form - a greenhouse gas which is a key component of smog and directly linked to increases in mortality.

Ethane and propane escape into the air from leaks during natural gas extraction and distribution, including from fracking - the process of drilling down into the earth and fracturing rock to extract shale gas. This new study shows that global fossil fuel emissions of these hydrocarbons have been underestimated and are a factor of 2-3 times higher than previously thought.

The authors of the international study involving researchers from York, Oslo and Colorado are now calling for further investigation into of methane, a potent which is emitted along with and propane from natural gas sources.

Co-author of the study, Professor Lucy Carpenter from the Department of Chemistry at the University of York, said: "We know that a major source of ethane and propane in the is from "fugitive" or unintentional escaping emissions during fossil fuel extraction and distribution. If ethane and propane are being released at greater rates than we thought, then we also need to carefully re-evaluate how much of the recent growth of methane in the atmosphere may also have come from oil and natural gas development. The current policy case for fracking, for example, is partly based on the belief that it is less polluting that coal."

The study used data collected from 20 observatories world-wide. The researchers from the University of York provided high-resolution data from a monitoring station in Cape Verde - a crucial location in the Atlantic which captures air blown over the Sahara, from North America, the Middle East and North Africa.

Like other hydrocarbons, when ethane and propane mix with nitrogen oxides from vehicles and power plants they form ozone in the troposphere - the lowest layer of the atmosphere that constitutes the air we breathe. While ozone in the Earth's second layer of atmosphere - the stratosphere - is desirable, ground level ozone has damaging consequences for ecosystems and human health.

Scientists need to understand accurately the levels of hydrocarbons in the atmosphere to predict the exposure of populations to ozone. This is particularly important for some suburban and rural areas which are already known to be on the edge of the limits of safe exposure.

Professor Ally Lewis, a co-author of the study from the Department of Chemistry at the University of York added: "Levels of ethane and propane declined in many places the 1980s and 1990s, but global growth in demand for means these trends may be reversing. The effects of higher ozone would be felt in the rural environment where it damages crops and plants, and in cities on human health.

"Tropospheric ozone causes a variety of serious health complaints and along with particulate matter and nitrogen dioxide is one of the three major causes of pollution-related deaths."

Explore further

Global ethane concentrations rising again, study says

More information: Stig B. Dalsøren et al, Discrepancy between simulated and observed ethane and propane levels explained by underestimated fossil emissions, Nature Geoscience (2018). DOI: 10.1038/s41561-018-0073-0
Journal information: Nature Geoscience

Provided by University of York
Citation: Global fossil fuel emissions of hydrocarbons are underestimated (2018, February 26) retrieved 23 October 2019 from
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Feb 26, 2018
As it turns out, this is one of the very reasons why Sir Dick Cheney and Co lobbied for so long, behind closed doors --and in secret-- to exempt "unconventional development" --aka fracking-- from all the clean air and water regulations, prior to the massive rollout of the technology, which, until then, was flying pretty much under the radar of public understanding, and therefore easily foisted upon us without adequate review or regulation.

Feb 26, 2018
Fracking is predominantly regulated by the states and they are more tightly regulated than federal law requires. Even Pennsylvania which has the weakest regulations is tough.

There are federal regulations on vertical drilling. Vertical fracking has been used for many many decades. Fed regs apply to horizontal drilling. All well heads look the same.

Where is the beef? What is the crime?

Where is the exemption in federal law?

Feb 26, 2018
So your are asking to find what doesn't exist in administrative/regulatory law? Have you every poured through that crap?

Who is the "mainstream ignorant sheep" and useful idiot?

Feb 26, 2018
Perhaps you might do that and contradict my argument, as I'm not going to do that.

Feb 26, 2018
I left something out. Exemptions are written into the Code of Federal Regulations (Law). See the tax code. That is the way special interests screw us and the swamp mobsters get rich.

Feb 26, 2018
I'd rather fossil fuel swamp monsters get rich rather than 'green' swamp monsters. At least the fossil fuel swamp monsters provide useful services and products compared to the unicorn promises of the green swamp monsters.

Feb 26, 2018
Them ain't unicorns on my roof powering my household and two electric vehicles tblakely.

And I do not rely on no stinking gasoline for transportation, pumping put pollution, . . neither!

How about you?

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