It was reported that during the second half of 2011, a lot of people all over the planet complained about hearing really weird humming sounds coming up from the sky. They have described those sounds as high-pitched noises that resembles the sounds from a loud engine, a rumbling, the slamming metallic door or groaning, etc.
One video uploaded from YouTube is said to have that strange apocalyptic sound and vibe that can make anyone feel uneasy. Here's the video description from the video-sharing site:
Warning: Strange weather events increasing around the world 2015 something is going on extreme weather tornado strange boom mystery dust storm weather thunderstorms hail wind rain fire climate chaos floods waves uk storm of the century freeze lava snow blizzard sinkhole December 2014 end of earth 2014 earth changes world events mass animal deaths.Watch the video here: