It’s written in the first two paragraphs of the article:
The 2022 explosion and leak of the Nord Stream pipeline in the Baltic Sea resulted in the release of 485,000 tonnes of methane into the atmosphere, according to a new study of the disaster.
The methane released from the pipeline was the largest human-caused methane emissions event in history. But the magnitude of the release is twice as bad as previously thought, according to a new study conducted by the United Nations Environment Programme and published in Nature. Prior studies estimated the methane released from the disaster at between 75,000 and 230,000 tonnes.
So what’s the “twice” in the article eh?
It’s written in the first two paragraphs of the article:
You’re just thinking twice as bad means twice as much, that’s just sloppy writing.
Edit that should be “at least twice as much” too.