409
xkcd #3121: Kite Incident
(imgs.xkcd.com)
Title text:
Detectives say the key to tracking down the source of the kites was a large wall map covered in thumbtacks and string. 'It's the first time that method has ever actually worked,' said a spokesperson.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3121/
I think OP means it's above on a map, i.e. north, like how the Mediterranean is above Africa.
Edit: to head off any pedants: there are jet streams in the south too, but the point was that the length would be less than Earth's circumference (plus xkcd comics seem to be set in north America).