The only problem with this is that natural gas, of course, is largely methane, which is the most potent greenhouse gas we know and there's a lot of leakage of methane in that whole export process. There's especially a lot of methane leakage when you're using unconventional methods, fracking, to extract the natural gas.
When you take all of that into account, this study shows there's a good possibility that the greenhouse gas impact on an LNG export business from Canada to China will actually make things worse.