紐西蘭上空的阿斯佩裡塔斯雲
Asperitas Clouds Over New Zealand
來源：Witta Priester｜發表日期：2025-08-17
這些是什麼雲？雖然目前還不知道它們的成因，但這種不尋常的大氣結構雖然看起來來勢洶洶，但似乎並不是氣象厄運的預兆。直到去年才被正式確認為一種獨特的雲型別，asperitas 雲在外觀上令人驚歎，在出現上也很不尋常，而且相對來說還沒有被研究過。大多數低雲層都是平底的，而asperitas 雲的底部似乎有明顯的垂直結構。因此，推測阿斯佩裡塔斯雲可能與在山脈附近形成的透鏡狀雲、或與雷暴有關的乳狀雲、或也許是一種從山上吹下的乾燥向下風（foehn）有關。這種風產生的雲被稱為坎特伯雷拱流，流向紐西蘭南島的東海岸。這張特寫圖片於 2005 年在紐西蘭坎特伯雷的漢默溫泉上方拍攝，之所以能顯示出很好的細節，部分原因是陽光從側面照亮了起伏的雲層。
原文：What kind of clouds are these? Although their cause is presently unknown, such unusual atmospheric structures, as menacing as they might seem, do not appear to be harbingers of meteorological doom. Formally recognized as a distinct cloud type only last year, asperitas clouds can be stunning in appearance, unusual in occurrence, and are relatively unstudied. Whereas most low cloud decks are flat bottomed, asperitas clouds appear to have significant vertical structure underneath. Speculation therefore holds that asperitas clouds might be related to lenticular clouds that form near mountains, or mammatus clouds associated with thunderstorms, or perhaps a foehn -- a type of dry downward wind that flows off mountains. Clouds from such a wind called the Canterbury arch stream toward the east coast of New Zealand's South Island. The featured image, taken above Hanmer Springs in Canterbury, New Zealand in 2005, shows great detail partly because sunlight illuminates the undulating clouds from the side.
※ 本文由萌芽機器人自動轉貼自每日一天文圖（Astronomy Picture of the Day，APOD），原文為英文，正體中文是透過 DeepL 翻譯及 OpenCC 進行自動處理，內容僅供參考，若有任何錯誤之處還請見諒！
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