Two years ago the world turned its attention to the Gulf of Mexico and the tragedy that was unfolding there, with the explosion of the Deepwater Horizon drilling platform. This disaster brought a reinvigorated focus to the safety of offshore drilling, but the term safety must now be understood to not just cover spills and leaks, but also the impacts that drilling has on the climate, especially when done in the fragile environment of the Arctic.
It is well understood that carbon dioxide emissions from fossil fuel combustion in our cars and power plants are responsible for the majority of earth’s global warming. Less appreciated, though, is that methane emissions account for nearly half as much of the warming we are currently experiencing as carbon dioxide. The oil and natural gas industries are the largest source of methane emissions from the US. Oil and gas extraction can also be significant sources of black carbon, another potent climate pollutant.
Changing technology and climate change itself, with receding Arctic ice, have made oil and gas production activities in the Arctic region more feasible. This trend is expected to accelerate, with the potential for vastly more methane and black carbon emissions. According to the United States Geological Survey (USGS), the Arctic holds one-fifth of the world’s undiscovered, recoverable oil and natural gas. As the ice retreats, oil and gas developers are moving in to exploit previously hard-to-access resources. Melting has also enabled increased shipping activity through the region, further elevating concerns over emissions in the region.
The Arctic is particularly vulnerable to climate change impacts, where, according to the Intergovernmental Panel on Global Climate Change (IPCC), Arctic temperatures have increased at about twice the global average rate over the past 100 years. September 2011 represented the largest retreat of Arctic sea ice on record, opening wider the fabled Northwest Passage to ship traffic.
Methane is an extremely potent climate pollutant, packing 25 times the punch of carbon dioxide when compared over a 100-year lifetime and 72 times its potency over a 20-year lifetime. Natural gas and oil production is one of the largest human-caused sources of methane, representing 20% of global anthropogenic methane emissions. Black carbon too, punches above its weight as a climate pollutant, but its major impact in the Arctic is hastening melting by depositing heat-absorbing black soot on white ice surfaces. Emissions from gas flaring, diesel engines, and shipping associated with gas and oil operations also represent potentially large in-region sources of black carbon. If oil and gas production is to occur in the Arctic, we must ensure that emissions of CO2, methane and black carbon are held to a bare minimum.
While oil production is the primary focus of current exploration and production activities due to high oil prices, natural gas is almost always produced along with oil, posing the problem of what to do with it. Crude oil usually contains some amount of “associated” natural gas that is dissolved in the oil or exists as a cap of free gas above the oil in the geological formation. In some cases, this represents a large volume of gas. For example, nearly 3 trillion cubic feet (Tcf) per year of gas is produced in association with oil in Alaska. The largest potential source (but by no means the only) of either methane or black carbon from oil production is the disposition of this “associated” natural gas.
When pipelines are available, the natural gas can be delivered to industrial, commercial and residential consumers. If there is no pipeline to bring the gas to market and no local use for the gas, then the “stranded” gas has little economic value and is often flared. While flaring the associated gas destroys most of the methane, it also creates a large source of CO2 and can create black carbon. Estimates of the volume of associated gas flared are substantial, with estimates showing as much as 5.3 trillion cubic feet of gas being flared each year. That’s about 25 percent of the US’s annual natural gas consumption. This leads to the release of approximately 400 million tons of CO2 per year, the equivalent to the emissions from over 70 million cars.
Fortunately, technologies and best practices exist to reduce the impact of oil and gas production. If we are going to extract the oil from the Arctic, we must do it in a way that does not exacerbate the very real problem that climate change is already posing there. In order to do so, the US should take the lead in ensuring that only the best practices are acceptable when it comes to Arctic exploration and drilling. The technologies and practices below can dramatically reduce the emissions associated with oil and natural gas, in some cases by 100%.
First, we need better characterization of emissions in the region, and better monitoring and reporting information. Methane and black carbon emissions from oil and natural gas production, especially in the Arctic, are not well characterized. Establishing standardized monitoring and reporting protocols, backed by legislation, is essential to quantifying these emissions and then adopting the best mitigation techniques.
Second, we must deal with the methane and black carbon from associated gas and well completions.
This means capturing all associated and completion gas (i.e., no venting). Where feasible, all gas should be sent to consumers through pipelines or LNG or beneficially consumed on-site or locally (for power generation or thermal or feedstock uses). Or, where geologically feasible, we should require reinjection of the gas into underground reservoirs. When there is no reasonable alternative to flaring, we should require the use of efficient flares.
Next, we need to deal with vented and fugitive methane emissions. Here we need vapor recovery units on storage, process tanks and floating production, storage and offloading units. Operators should use compressed air or electric control systems rather than pneumatic controllers, mitigation of methane emissions from all dehydrators should be required, and the use of wet seal compressors without gas capture systems should be prohibited. To detect leaks and equipment failures, we should require inspection and maintenance programs for all facilities operating in the Arctic.
Finally, for the mitigation of black carbon emissions, we should require ultra low sulfur diesel (ULSD) and Diesel Particulate Filters (DPF) for all stationary engines and small ships – either new or retrofit. And we should push to establish International Maritime Organization requirements for BC emission reductions for international shipping affecting the Arctic.
The opening of the Arctic to increased oil and gas development is a cause for concern. The Arctic is already being hammered by climate change and other environmental impacts. If we are on the verge of an Arctic oil and gas rush, this will only add to the issues facing this fragile environment. If we implement the above policies domestically, and pressure our other Arctic neighbors to do the same, we will greatly reduce, but certainly not eliminate, the air and climate impacts of oil and gas development in the Arctic.