As for Alaska:
When I was at Soil Science Institute a few years ago, which then was held at Washington State University, on of the professors had a large poster of an aerial photograph of those formations on the North Slope. They look EXACTLY llike Carolina Bays. I saw the poster from a distance, and thinking it was of Carolina Bays, walked up to have a look..and was surprised to find the photo was of Alaska.
If I recall correctly, the geomorphic surface upon which these Alaskan Bays reside is younger (i.e., Holocene) than the ones currently supporting bays in the Carolinas. This is larglely an artifact of Holocene marine transgressions in the Southeast US; if you drill down through the various stranded barrier dunes and back-barrier flats along the coast of South Carolina today, you will find buried carolina bays.
Well, not entirely. The Alaska "bays" are not nearly as uniform in shape or length/width dimensions. Seems the folks studying the Alaska bays haven't reached a conclusion yet as to what actually creates their bays either. Butt crack ice(cracking the bedrock) and thawing seems to be the most widely accepted hypothesis.
...if you drill down through the various stranded barrier dunes and back-barrier flats along the coast of South Carolina today, you will find buried carolina bays.
You're talking barrier islands/strips? Backfilled by wave action? Hurricanes? Tusnamis? Rising oceans? Even so, does that necessarily rule out aerial fireworks? Like I said, you'll need to go slow with this ol' East Texas country boy ;^)
BTW, I'm sure you're familiar with the other "bays" around the world. After doing some additional searching, there seems to be a bunch of these things around. MANY of them nowhere near a present or historic/prehistoric shoreline. Some aligned parallel with a shoreline; some at elevations of a thousand feet; maybe more. Thoughts? Best I can tell the one thing they seem to have in common is they have been located(the visible ones?) on soft soil. Sandy lome and the like??? I suppose if sand dunes didn't change so much they might be good candidates for finding visible bays.
This is giving me a headache. Think I'll take a nap.