Updated

Somewhat hidden among the alarming data about global warming and environmental horribles is a significant piece of good news that seems to have slipped by with little attention. International and American agencies charged with keeping track of carbon pollution each report that while global air pollution is on the rise, U.S. emissions have reduced significantly in recent years.

The International Energy Agency in 2012 reported that U.S. carbon emissions declined from the previous year and also were down an astounding 7.7 percent since 2006.  That's the largest reduction from any country on the planet. A similar finding from the U.S. Department of Energy concluded that carbon emissions in the first quarter of 2012 were at their lowest point in two decades.

A significant reason for the reduction may also explain why this hasn't been widely noted.

"It's underreported because it's not wind and solar; it's natural gas and that's still a fossil fuel," Heritage Foundation's Nick Loris said.

The IEA says America's move toward increased production of natural gas is a major reason for the reduction.

"It has been underreported that [natural gas has] usurped coal as the biggest electricity provider and has substantially reduced emissions as well," Loris said. "[T]he fact that it's gone underreported is certainly glaring in terms of the environmentalist movement."

It's also noteworthy that the reduction has occurred in the absence of a controversial cap and trade law or U.S. participation in United Nations-backed climate compacts.

The Sierra Club doesn't dispute the numbers or the causes for the carbon reduction -- the IEA also says the economic downturn with fewer cars and trucks on the roads played a role -- but it rejects the notion that the relative environmental benefits of natural gas should be seen as long term positive development.

"What we do know is that gas when you compare gas to clean energy, it actually hinders our efforts to fight climate change," Sierra Club's Michael Brune told Fox News. "And it hinders our efforts to change to a clean energy economy."

The raw data reveals a steady increase of natural gas withdrawals in the U.S. from 24.6 million cubic feet in 2007 to 29.7 million in 2012.  Meanwhile the amount of coal extracted over that same time dropped by ten percent. To be sure, the country has seen an economic slowdown during the time period.

The federal government's Energy Information Administration calls natural gas the least carbon-intensive fossil fuel. It also produces the smallest amount of carbon dioxide emissions, which are linked to global warming.  The agency also concludes that power plants burning natural gas are usually more efficient than their coal-fired counterparts; another reason for the drop in emissions.

While the numbers may be new to many people, they're not new to Adam Berig, head of air quality for the energy company Encana.

"I think that is widely known in the industry," Berig told Fox News at a production well near Boulder, Colorado. "We talk about that within our own company and I think that we're always driving...to reduce emissions--to bring down any sort of emissions that we can through new control technologies."

Berig explained to Fox News how Encana's modernized field equipment is used to extract the natural gas then transform it into a usable energy source.  The company's website says, "strong environmental performance is a key indicator of our success."

Berig offered a simpler business-oriented explanation for why Encana wants to keep pollutants out of the air.

"Those natural gas emissions -- we want to keep in the pipeline so we can use that product," he said.

The Sierra Club says studies from several years ago showing a significant reduction in carbon emissions from coal to natural gas are overstated.    Brune points to the fracking process as responsible for the natural gas boom as more greenhouse gas intensive than normal drilling.  Additionally, he says, the movement of natural gas once it's out of the ground and moved through pipes harms the environment more than thought.

"And so all of that adds up to a whole lot of pollution which minimizes the advantage between coal and gas," he said.

Those claims are rejected by the industry which touts natural gas as an affordable long term energy source that minimizes environmental harm. But Sierra Club and other like-minded interests aren't satisfied with a reduced role of natural gas and are pushing hard on the Obama administration for more stringent environmental standards.

"[W]e do need some kind of comprehensive climate change legislation here in the United States," Brune said.  "If it doesn't happen this year it has to happen within the next few years in order to give us a fighting shot at arresting climate change."