Lena Höglund-Isaksson has some bad news: it turns out that global oil production released a lot more methane into the atmosphere than previously thought.
A study she was the lead author of has just been published in the journal Environmental Research Letters, and in that study she blows the top off a decades old formula that vastly understated methane emissions from oil mining.
Ms. Höglund-Isaksson explained that, “In an oil reservoir, there is a layer of gas above the oil which has a methane content of 50 to 85 percent. When you pump the oil to the surface this associated gas will also escape,”
Methane is an important greenhouse gas to monitor, and scientists consider it the second-most important contributor to climate change. Carbon dioxide is clearly the most important gas for us to reduce the emission of, but the use of formulas that drastically understate the production of methane is simply unacceptable.
Atmospheric concentrations of methane can be measured easily, but it is hard for us to know the source of that methane. Animals also produce large amounts of methane and when we use such misleading formulas to estimate the contribution of petrochemicals, we are clearly deluding ourselves to its dangers.
In North American oil production infrastructure, most of the methane is not allowed to escape into the atmosphere, and what can’t be recovered is flared to prevent leakage or explosions.
A small fraction of the methane in North America is simply vented, but in other parts of the world where recovery rates are poorer larger amounts of the gas are simply allowed to be shot into the atmosphere.
“Existing global bottom-up emission inventories of methane used rather simplistic approaches for estimating methane from oil production, merely taking the few direct measurements that exist from North American oil fields and scaling them with oil production worldwide,” explained Ms. Höglund-Isaksson.
This methodology was extremely flawed, and Ms. Höglund-Isaksson developed a more accurate way to estimate the release of methane into the atmosphere.
Once she applied her new formulas to the existing data, it was revealed that in the 1980s global methane emissions were much, much higher than previously thought. These emissions were due largely to the Russian oil industry, as they spew a large amount of methane into the fragile atmosphere.
On a seemingly positive note, Ms. Höglund-Isaksson found that methane recovery is becoming more effective. Since 2005 emissions from oil and gas systems have remained fairly constant, and she cites increasing shale gas production as the reason for this.
Unfortunately this a mixed blessing, at best.
Shale gas recovery is more commonly known as “fracking” and while lower in methane emissions, it is a much higher risk in other ways and is known to contaminate ground water.
The use of non-traditional means of oil recovery like shale mining also represents a rising desperation on the part of the oil producers, and is not a long term solution to our energy needs.
We need to look for ways to make holistic changes to our energy base, and not re-arrange the deck chairs the sinking ship that is fossil fuels.
[via eurekalert]
