Natural Gas: Now A Bridge to Climate Catastrophe

Press coverage of natural gas fracking controversies in Pennsylvania and other places where natural gas fracking has boomed in the last few decades has mostly focused on disputed claims about gas development’s adverse environmental impacts to water, air, forests, and land, while largely ignoring natural gas’ continuing contribution to ominously rising atmospheric greenhouse gas (GHG) concentrations.

When the natural gas fracking boom began about two decades ago, proponents of natural gas combustion often sold it as a “bridge fuel” for climate change because natural gas combustion only emits only 53% of the CO2 emitted by coal combustion provided that methane leakage from the gas production and distribution system is less than 3% of the produced gas. Although the actual amount of methane leakage from gas production remains somewhat contentious, even if there is no methane leakage from gas production, because the international community has understood for at least a decade that the world must move toward zero carbon emissions within several decades to prevent climate catastrophe, government action to replace natural gas with non-fossil energy should have been an imperative at least throughout the last decade of natural gas fracking expansion to make the transition to non-fossil energy needed to avoid planetary disaster feasible.

The failure to move quickly to non-fossil energy in the last decade is partially responsible for the rise of atmospheric CO2 to reach 415 ppm, a concentration never experienced in human history. Because even modest amounts of additional warming above current global elevated temperatures create the risk that certain thresholds, or “tipping points,” in the climate system may be exceeded causing much more abrupt climate change, human-induced climate change creates grave threats to life on Earth. For this reason, every country in the world agreed in Paris in 2015 to act to limit additional warming as close as possible to 1.5 0C but no more than 2.00 C.  

Yet, to achieve the Paris Agreement’s warming limit goals will require an “all hands on deck” by all governments at all levels to completely decarbonize their economies by 2045 to keep warming below 1.5 0C and by 2070 to achieve the 2.00 C limit. Making matters worse, when the 2.00 C goal was adopted in Paris, many scientists believed that achieving this warming limit would prevent abrupt climate change that would be caused if the Earth’s climate tipping points were exceeded. Yet, recent evidence has frightened many climate scientists because a few of the tipping points, including rapid increases in methane and CO2 emissions liberated when artic permafrost melts, are already beginning to appear, making the climate crisis a staggering global emergency.

Yet climate change is not only a horrific future calamity, the 1.1 0 C temperature rise the Earth has experienced since the beginning of the industrial revolution has already caused brutal suffering by causing increases in killer hurricanes, unprecedented flooding, droughts, forest fires, storm surges, climate refugees, increases in vector-borne and tropical diseases, killer heat stresses, loss of valued ecological systems including coral reefs around the world, and human conflict in Syria and parts of Africa. Because natural gas combustion has contributed to raising atmospheric GHG concentrations which is causing these horrors, nations have both a moral and legal duty under the “no harm principle,” a provision of customary international law agreed to by the United States in the 1992 United Nations climate convention to not harm citizens in other countries. Thus, all levels of government in the US must replace energy technologies which emit GHGs with technologies that don’t raise atmospheric GHG concentrations ASAP.

In addition, the two most compelling arguments that proponents of rapid natural gas expansion sometimes made in opposition to ambitious proposed policies that would replace fossil fuels with renewable energy are no longer viable if they ever were.  First, although at one time wind and solar energy were more expensive than gas, renewable energies are now competing favorably with fossil energy on cost. Second although renewable energies need backup sources of energy when the wind is not blowing or the sun is not shining, energy storage technologies including batteries, are rapidly improving in capacity while lowering price. This is the reason that growing numbers of national and local governments have set targets to achieve 100% renewable energy in the electricity sector and ambitious targets to replace fossil fuel powered vehicles with electrically powered transport in the next several decades.

For these reasons, Pennsylvania and other places where natural gas fracking has boomed must acknowledge that the only bridge that natural gas is now a bridge to is a bridge to world catastrophe and therefore must adopt policies to replace all fossil fuel technologies with technologies which don’t emit GHGs ASAP.


Donald A Brown

Scholar in Residence and Professor,

Sustainability Ethics and Law

Widener University Commonwealth Law School


US Media Fails to Educate The Public About Links Between Greater Natural Gas Use and Climate Change

methaneleakageThe New York Times and the Wall Street Journal  today reported on a new study by the University of Texas that found leakage rates of methane from natural gas fracking operations are lower than previously stated by US EPA. This report found that direct measurements of methane emissions from  190 onshore natural gas sites in the United States indicate that methane emissions from completed wells are are  lower than commonly thought although the report also acknowledged that emissions from pneumatic controllers and other equipment associated with natural gas production facilities were higher than previously estimated.

The report also concluded that taking into account the lower emissions from completed wells and the higher emissions from other equipment, actual methane emissions are most likely 20% lower than previously estimated.

This report has created a large buzz on the internet because at issue is whether natural gas is a bridge fuel to lower the threat of climate change. If the methane leakage rate is less than 3.6%, then it is widely assumed that natural gas is better than coal.  That is, if leakage levels are below this level it is generally assumed that switching to natural gas lowers the US carbon footprint and therefore greater natural gas production should be supported by citizens concerned about climate change. As a result the methane leakage rate issue has gathered enormous interest in climate change policy discussions.. Studies of methane leakage rates have reached widely different conclusions about actual leakage rates in part because different studies have used different: measurement methodologies, types of wells measured, portions of the the entire natural gas production process, and assumptions about leakage in the gas distribution process. The recent University of Texas study acknowledges that there are elements of the natural gas production to consumption cycle that were not fully considered.  And so, it is likely that scientific conclusions about methane leakage rates will continue to change from study to study in the next few years.

Because natural gas may produce less CO2 equivalent per unit of energy produced, natural gas companies are pushing natural gas as at least a short- to medium-term solution to climate change

Yet, as we have written about before, there is one extraordinary important issue about the link between natural gas production and climate change that is rarely being reported on in the US press nor is it usually part of the US debate about natural gas fracking and its impact on climate change.

The methane leakage debate usually assumes if the methane leakage rate is low enough, switching from coal to natural gas as fuel should be welcomed by proponents of action on climate change. Yet what is notably missing in the media discussion of this issue is the urgency of moving to non-fossil fuels or energy technologies that produce very, very low carbon emissions to give the world any hope of prevent catastrophic climate change.

We explained the  urgency of moving quickly to non-fossil energy in considerable detail in the recent entry on this website in  Ethical Issues with Relying on Natural Gas as a Solution  to Climate Change

Even if natural gas combustion creates approaching 50 percent less CO2 equivalent per unit of energy produced, an amount which is well beyond best case on ghg emission reductions,  it will not create the much greater emissions reductions necessary in the next 30 years to give any hope of  limiting warming from exceeding levels that will cause catastrophic impacts.  In short, natural gas combustion can’t produce the the emissions reductions that are needed just a few decades to put the world on a safe ghg emissions pathway.  Also investment in natural gas facilities may delay the needed rapid switch to non-fossil fuels. Although natural gas switching might help reduce the threat of climate change threat if  methane leakage rates are at the lower end of the range discussed  in the scientific literature in the very short term, the world needs massive investment in non-fossil technology as soon as possible.

In addition if coal combustion were to be replaced now by non-fossil fuel energy, it would help immediately much more than conversion of coal to natural gas combustion does in putting the world on an urgently needed ghg emissions reduction pathway needed to prevent catastrophic warming.

nw book advIn addition, large investments in natural gas combustion facilities will likely make it harder to switch to non-fossil energy because these investors will likely demand a return on their investment in the natural gas plants before they are shut down.

Large investment in cheaper natural gas may also increase energy demand to levels that result in greater total releases of ghgs even assuming that natural gas produces less CO2 equivalent on a BTU basis than coal.

It is simply irresponsible for the US media to report on the methane leakage issue without explaining the urgency of moving to non-fossil energy.

Of great concern, some natural gas companies are on the one hand claiming that natural gas is better for the climate change while they fight legislation to increase the US share of renewable energy.  A strong ethical case can be made that any political support for natural gas as a short-term bridge fuel  should be conditioned on the natural gas industry promising to stop lobbying against rapid scale up of renewable energy programs.


Donald A. Brown

Scholar In Residence, Sustainability Ethics and Law,
Widener University School of Law
Visiting Professor, Nogoya University, Nogoya. Japan