You're right, electrified lines are very good. The majority of Amtrak's routes are diesel.
I don't keep notes on where I read what, but this BBC article is fairly thorough, and puts electric trains at 40 grams carbon per passenger mile, diesel trains at 90g, long haul flights at 102g, and short flights at 133g. It mentions that occupancy is a factor but doesn't say if those numbers assume full occupancy or are averaged out over actual ridership.
Routes but not passenger trips. The NEC has 260M passenger rail trips per year. Amtrak has 32M on its entire system 17M of which are on the electrified NEC. The diesel routes compete with cruise ships. They’re lovely but they’re not a transportation solution.
I don't keep notes on where I read what, but this BBC article is fairly thorough, and puts electric trains at 40 grams carbon per passenger mile, diesel trains at 90g, long haul flights at 102g, and short flights at 133g. It mentions that occupancy is a factor but doesn't say if those numbers assume full occupancy or are averaged out over actual ridership.
https://www.bbc.com/news/science-environment-49349566