Highland. Lowland. Island.
Varieties from the same region share characteristics, but they're distinct from each other.
I'm curious how historically the kilns would be fired across Scotland, if peat was more prevalent?
http://www.bairds-malt.co.uk/Bairds-Malt/Process/process mentions about using hot air.
https://www.laphroaig.com/en/whisky/our-process - Has some nice videos, including them using solely peat to kiln the malt.
As well as the fact that irish whiskey generally has a mashbill containing a portion of unmalted barley. Not sure, but I think it is at _least_ 30% as per the Irish Whiskey Association rules?
Single malt Scotch requires (as per SWA rules) a 100% malted barley mashbill.
Blended Scotch, on the other hand, has no such requirement, and is typically a blend of Single malt Scotch and alcohols from other cereals.