Technically you should write it blaahaj instead (if writing Norwegian or Danish, that is). Before the adoption of the Swedish å, aa used to be used in Norway and Denmark for the same sound.

[–] hungryphrog@lemmy.blahaj.zone 8 points 12 hours ago (1 children)

So that's why it looks similar to a or ä. I've always wondered that if it makes an o sound, why doesn't it look like an O.

[–] Successful_Try543@feddit.org 1 points 29 minutes ago* (last edited 18 minutes ago)

Historically, 'Å' was an 'A' with an additional 'a' on top. This has evilved into becoming the '°'. Similarly, 'Ä' was an 'A' with an 'e' on top, which evolved into becoming two dots.
Interestingly, these umlauts are treated as extra characters in the Nordics but in German they aren't. That's why Swedish dictionaries are sorted from 'A-Ö' while German ones are 'A-Z'. So in order to find German Ärger or Swedish ängen, you need to look at different spots in the dictionary ('Ä' -> 'Ae' (1st letter of the German alphabet) vs. 'Ä' (28th letter of the Swedish alphabet).