Proposed new and expanded pipelines that would pump natural gas from the fracking hub in the Appalachian Basin to power plants and other consumers throughout much of the eastern half of the U.S. will commit the country to high carbon emissions. That level will be too high for the U.S. to meet its climate goals, according to a report by the environmental advocacy group Oil Change International.

Collectively, the 19 pending pipeline projects would enable a doubling of natural gas production from the Marcellus and Utica shale formations of Pennsylvania, Ohio and West Virginia, according to the study published last Friday on the group's website. It was endorsed by 11 other environmental groups, including the Sierra Club, Earthworks and 350.org.

The climate impact of those projects—and the new gas-fired power plants that they would serve—would come from locking in unsustainable levels of carbon emissions for decades to come, the report concluded. The findings called into question the common claim by energy executives and politicians that natural gas is a "bridge fuel" to a clean energy future.

"Expanding gas production is a bridge to climate disaster," said Stephen Kretzmann, executive director of Oil Change International.

The report called for a climate test in the federal permitting process of all fossil fuel projects to ensure that they fit within national climate policies.

"We have a very firm, compelling international goal of 2 degrees or as close to 1.5 degrees as we can get it, and we are making energy decisions every day that aren't being measured against that goal," Kretzmann said.

Industry officials, who champion natural gas's low emissions compared to coal, disagree. "America continues to lead the world in the reduction of carbon emissions due in part to clean-burning natural gas," American Petroleum Institute president Jack Gerard said in a statement this week.

The current U.S. climate target—which may not be enough to help achieve the international goal of limiting global warming to below 2 degrees Celsius —is an emissions reduction of 83 percent from 2005 levels by 2050. The study concludes that going forward with the proposed pipeline projects in the Appalachian Basin would make meeting the national goals impossible.

When he rejected the Keystone XL pipeline last November, President Obama cited the climate impact of the project, which would have carried tar sands crude from Canada to Gulf Coast refineries. Environmental advocates have since called for a similar climate test on all fossil fuel projects. Similar language was included in the 2016 Democratic Party platform.

In the absence of such a climate test, infrastructure projects like the proposed gas pipelines become the nation's de facto energy policy because they lock in energy sources, and their related emissions, for decades.

"Once the initial investments have been made, there is very little incentive to turn them off and there is lots of incentive for new producers who can now more cheaply get their fracked product to market," Kretzmann said. "It triggers additional production."

The assessment conservatively assumed that the natural gas industry could successfully reduce emissions of methane, a potent greenhouse gas and the primary component of natural gas, by 45 percent. That is the ambitious target recently set by the Obama administration.

Even if methane is reduced that much, "this still isn't remotely on track for being consistent with a climate-safe future," Kretzmann said.

Additional pipelines that transport gas to markets even further afield could foster additional gas production and increase emissions. One project that has received strong opposition for its outsized climate impact is a series of three upgrades or expansions to Spectra Energy's Algonquin Gas Transmission pipeline from New Jersey to eastern Massachusetts. It would increase the capacity to transport gas along that route by 40 percent.

"I think that just goes to show that this paper is looking at the beginning of the problem and there are even more impactful pipeline expansions across the country," said Caitlin Peale Sloan, an attorney with Massachusetts based environmental advocacy group Conservation Law Foundation.

Sloan said increasing natural gas capacity conflicts with state legislation that commits Massachusetts to an 80 percent reduction in greenhouse gas emissions from 1990 levels by 2050.

"We have to decarbonize our electric grid by 2050 to meet economy-wide requirements and stranding ourselves at the natural gas emissions level is untenable," she said.

Fossil fuel-promoting infrastructure projects are not limited to natural gas or to pipelines. TransCanada, the company behind the now-rejected Keystone XL pipeline, is pushing for Energy East, another pipeline that would bring tar sands crude to ports in eastern Canada. From there, an annual parade of nearly 300 supertankers would form a "waterborne pipeline" down the eastern seaboard to Gulf Coast refineries, according to a report published Tuesday by the Natural Resources Defense Council.

That report said the combination of tankers and a pipeline would have a huge climate impact.

"The production, transport, and consumption of oil from Energy East would emit as much annual greenhouse gas as 54 million passenger vehicles—the equivalent of all registered vehicles on the road in Germany," the study said.

The report called for the Canadian government to evaluate the climate impact as well as the potential impact on the marine environment in Canadian and U.S. waters.

"What you are seeing is business as usual, the expansion of oil and gas production with no real consideration of the climate impacts," said Charlie Cray, a senior research specialist at Greenpeace, who was not involved in either report. "That is a significant obstacle to the acceleration of the clean energy revolution."