“Whether LNG is better for the climate than other options is a topic of intense debate. If it replaces coal, then in general, yes. Since it’s made mostly of methane, it burns more cleanly than coal, producing roughly half of the greenhouse gas emissions. But it’s still a fossil fuel that contributes to warming, and every new gas terminal, transport tanker, and power plant implies these emissions will continue for decades more.
By one estimate, US LNG shipments to China reduced the intensity of greenhouse gas emissions — the amount of greenhouse gases released per unit of energy — by as much as 57 percent. Other analyses have also found that countries that import LNG produce power with lower emissions than with local coal. Another advantage is that gas produces fewer air polluting substances like particulates, so turning away from coal has immediate health benefits. And having more cheap gas on the global market could undermine the case for new coal power plants in some countries, if they can secure a reliable gas supplier.
But some environmental activists say this paints too optimistic a picture. For gas importers like the United Kingdom, LNG has a greenhouse gas footprint four times larger than gas extracted locally. Methane is itself a heat-trapping gas, about 30 times more potent than carbon dioxide, so small leaks from gas infrastructure — as little as 0.2 percent — can quickly overwhelm any environmental advantages. The added steps of chilling and shipping gas create even more opportunities for LNG to escape, and the industry has done a poor job of tracking its fugitive emissions. In addition, some LNG exports will simply fill in existing gas needs, as they do in parts of Europe, so the climate impact overall is at best a wash, though likely worse than more locally produced gas. At the same time, renewable energy is already the cheapest source of electricity in many parts of the world, and climate activists argue that gas no longer serves as a bridge to a low-carbon world.”
https://www.vox.com/climate/24055711/lng-export-pause-biden-liquefied-natural-gas-climate-change