
Surreal scenes look like someone split the skies in two.
Summer in Japan is hot and humid, but winter is the exact opposite, cold and dry, for most of the country. Typical winter weather is a chill in the air and hardly a cloud in the sky, but residents of west Japan woke up to something different on Tuesday.
朝うわなにこれと思って
— な っ ぱ 🌱 (@_wahu_wahu_) December 21, 2021
写真撮ったけど、これ地震雲なの…?
しかも瀬戸内地域だけとか怖いんだけど pic.twitter.com/2nRqSe14wF
Sure, you could say the sky was clear and blue, but only up to a point, or, more accurately a line. In many of the prefectures grouped around the western end of the Seto Inland Sea, it looked like someone had used a ruler to draw a division between two different atmospheric motifs.
https://twitter.com/elm_r3r/status/1473203873204805636Or, alternatively, if your prefer your art of the digital variety, it seemed like the sky was glitching and not fully loading its graphical assets.
https://twitter.com/Po9n1x/status/1473150222109147138This wasn’t some small, ultra-localized phenomenon, either, as Twitter users from as far west as Fukuoka and as far east as Okayama, in towns on three of Japan’s main islands (Honshu, Shikoku, and Kyushu), posted photos and videos, like this one from the town of Fukuyama, Hiroshima Prefecture, that came with the question “Who cut the sky in half?”
https://twitter.com/Xyato7/status/1473286370873720834誰が切った? pic.twitter.com/dfxxzG17zG
— IRON FACTORY IKEDA (@IRON_IKEDA) December 20, 2021
Depending on both your personal aesthetic and geographical perspectives, you could find these unusual clouds beautiful…
今朝の空 何年見上げても見れない空
— 炭水化物 (@LfSOM8De2Zr1c36) December 21, 2021
#地震雲 #いまそら #いまそら部 pic.twitter.com/tUgDjueSge
…or ominous…
https://twitter.com/Qzy172/status/1473216027316355075…but it was the latter for more than a few Japanese Twitter users, who referred to these conditions as jishingumo, or “earthquake clouds.” Among those who subscribe to the theory, large, low-altitude clouds like these that retain their shape and position for a long period of time are harbingers of an upcoming earthquake, causing some who were snapping photos to do so with a mix of wonder and unease.
▼ “These clouds in Okayama are beautiful and creepy…I hope nothing bad happens.”
岡山は美しくも不気味な雲。
— Hiroshi (@h_katsum) December 20, 2021
地震雲とかじゃないよね。
変なこと無ければ良いけど。#岡山 pic.twitter.com/VX0oIJI0ES
However, while jishingumo have been a part of Japanese folk wisdom for some time, scientists haven’t found any link between unusual cloud formations and subsequent seismic activity. Japanese meteorological organization Weather News was downright chipper as they discussed the clouds, cheerfully explaining that they’re the northern edge of a cloud front that was stretching southwest past Okinawa and all the way on to Taiwan, as shown on the satellite map in this video.
めちゃくちゃ珍しい雲。
— Takejiro@ドルGoldBTC買い投資家 (@takejiroabc1968) December 21, 2021
ひょっとして地震雲❓#珍しい雲 #地震雲 #地震雲かな #地震雲じゃないよね pic.twitter.com/nUTV2AVwBs
今日は、いつもと違う雲が
— パグのマヨ (@pagupagumayo6) December 20, 2021
出ているワン( ー̀дー́ )ムムッ…
地震雲 じゃないよね?!😱 pic.twitter.com/i1mZYesPpE
So while being earthquake-prepared is always a good idea in Japan, scientists don’t think the strange clouds in the sky are a precursor to the ground shaking.
Sources: Jin, Hachima Kiko, YouTube/ウェザーニュース, Wikipedia
Top image: Pakutaso (edited by SoraNews24)
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