[DenisM]

1. 15 miles one way. 30miles x 1.6km x 1.12kg/km x 250 days = 1440 kg

2. Few people will move form US to Germany. It's more likely someone will move e.g. from Portland to San Diego. 275kg roundtrip, 550kg adjusted for radiative forcing.

So if you fly 3 times per year it's a wash, if you fly 6 times a year it's double the CO2 emission.