The sounds heard over scandinavia, also.

reply to post by Sorgmodig


I think many of these sounds come from new drilling techniques for oil and gas, "fracking". There are many drills and pumps involved---and at night (when other noises have died down), and during certain atmospheric conditions, they could sound pretty loud.

Petroleum companies don't run on a 9-5 schedule---once they've committed the capital to start a well, the clock is ticking, they want to bring it onto production as soon as possible.

I made some new recordings, this time with a video camera.
www.youtube.com...

Yes, I will film all around the next time like the guy in the comments posted.
But what are your thoughts on this?
My theory is that birds that travel in flocks(i don't know if it's the right word) are making these sounds.