A fuel pump attendant stands on the forecourt of a gas station operated by Royal Dutch Shell Plc in Clacton-on-Sea, U.K., on Wednesday, April 8, 2015. Shell agreed to buy BG Group Plc for about 47 billion pounds ($70 billion) in cash and shares, the oil and gas industry’s biggest deal in at least a decade. Photographer: Chris Ratcliffe/Bloomberg

In an interview last year, Ben van Beurden, the new CEO of oil giant Royal Dutch Shell, gave his outlook on what it would take to deal with the global problem of carbon emissions.

“I think the real challenge is not so much how do we accelerate renewables but more about how do we decarbonize the system we have,” said van Beurden. “How do we take coal out and replace it with gas?”

Shell made a major step in that direction Wednesday, announcing the acquisition of BG Group, a corporate descendant of British Gas and a leader in global liquefied natural gas or LNG sales — a market that is expected to grow considerably in the next decade.

The deal, valued at around $70 billion, represents the biggest purchase of an exploration and production company in history, the investment advisory firm Raymond James said in a note to investors. “This acquisition will be a historic precedent as it will exceed the current record E&P transaction value when Exxon bought XTO Energy in 2009 for $41 billion,” it said.

The deal also positions Shell, already the world’s leader in the liquefied natural gas market, even further ahead. By acquiring BG, it is getting the fifth largest player in the space.

“They’re already number one, and this would make them twice the size of their nearest competitor, which is ExxonMobil,” says Brian Youngberg, an energy analyst at Edward Jones.

That’s a good position to be in at a time when climate and pollution concerns are driving a shift from coal to natural gas in nations as diverse as the U.S. and China.

Renewable energy doesn’t contribute any carbon dioxide emissions — and burning coal produces the most among fossil fuels. But nestled in between is natural gas, which, when burned, produces about half as much of the greenhouse gas as coal. That’s why it has often been touted as a “bridge fuel” to a low carbon future.

LNG, or liquefied natural gas, is a method of turning natural gas or methane into a liquid form so that it can be transported by tanker, rather than by land-based pipelines — thus allowing for a much broader global distribution of hydrocarbon resources that may be found far from where they’re sold.

In a joint presentation making the case for the deal, Shell noted that acquiring BG would “enhance” its position not only in liquefied natural gas but in another key growth area for the company, deep water oil exploration. In particular, the move, noted Shell CEO van Beurden on a call discussing the merger, will make Shell an immediate major player in the Brazilian deep water market, thanks to BG’s assets there.

BG has also succeeded in recent years in replacing oil and gas reserves — a key industry metric — where Shell has struggled of late.

Perhaps the most important part of the story, however, may be how this helps to position Shell to sell huge volumes of LNG to China — a country lacking natural gas resources large enough to meet its fast-growing energy needs.

“It’s cheaper for them just to import it at the end of the day,” says Edward Jones’ Youngberg of China’s natural gas position. “For the last several years, pollution is becoming an issue, so they’re building a lot of nuclear and natural gas fueled power plants.”

In light of China’s pledge to peak its greenhouse gas emissions by around 2030, importing more natural gas also takes on greatly increased importance.

That’s where BG Group comes in. In its 2014 annual report, the company noted that two-thirds of its LNG sales were in the Asia Pacific region. The company also projected a dramatic growth in demand for LNG imports in India and China by 2025.

The company calls China “the world’s fastest-growing LNG market,” and says that by 2017 it expects to be its biggest LNG supplier.

“Across Asia, coal is still the dominant fuel for generating electricity,” notes BG’s website. “However, as increasingly prosperous urban populations demand cleaner air, we are seeing a shift to gas in the wealthier regions.”

Through this deal, then, Shell — which has an internal companywide carbon tax — has positioned itself to play a key role in helping sell the gas that will, in turn, help China to pursue its climate and pollution reduction goals and rely on fewer coal plants.

The creation of an even more massive LNG giant is also quite significant in the current geopolitical context. Right now, Europe sits right next to natural gas rich Russia, but in light of the conflict in Ukraine, is very wary of dependence on the country for energy. Instead, the new Shell will be able to sell gas throughout Europe that it transports from far afield.

“Europe is trying to diversify away from their reliance on Russia,” says Youngberg.