Taiwan’s longest-lasting rainbow breaks world record 破世界紀錄!台灣出現超狂九小時彩虹

Wed, Dec 06, 2017 - Page 14

The weather in Taipei last week was treacherous and changeable — one minute it was pouring, the next the sun was shining. On Thursday afternoon, a resplendent rainbow appeared over the city.

Due to the high elevation of Chinese Culture University (CCU) on Yangmingshan, Taipei, people on the campus enjoy a broad vista of the city. Chou Kun-hsuan and Liu Ching-hwang, professors of CCU’s Department of Atmospheric Sciences, said that this rainbow was clearly visible from 6:57 am to 3:55 pm on Thursday, meaning that it lasted a full eight hours and 58 minutes. Chou says that this rainbow has broken the six-hour world record observed in the UK in 1994, likely setting a world record for longest-lasting rainbow

Every winter, the northeast monsoon affects northeast Taiwan, and eastern Taipei, exposed to these winds, often has heavy rainfall. As the sun migrates west over the course of the day, it shines down on the eastern part of the city. When a sun’s ray hits an airborne water droplet, the ray will be refracted as it enters the droplet, reflected on the interior wall and then refracted once more as it exits. These two refractions and one reflection are what causes the rainbow.

Chou said that the rainbow in fact consists of four layers — in addition to the more obvious “rainbow” and its outer periphery, referred to as the “secondary rainbow,“ which is fainter than the rainbow itself and with some colors appearing in reverse order, there are also two “supernumerary rainbows” that are less distinct because of their size and location.

(Liberty Times, translated by Lin Lee-kai)

台北市的天氣上週詭譎多變,一下子大雨,一下子放晴,上週四下午還難得出現一道完整的彩虹!

文化大學校園位於陽明山,地勢高而視野廣闊。該校大氣科學系教授周昆炫及劉清煌觀測到,這道彩虹從週四早上六時五十七分至下午三時五十五分期間均清晰可見,時間長達八小時五十八分。周昆炫認為,這道長壽彩虹已經打破一九九四年在英國所觀測到的六小時彩虹,成為彩虹持續時間最久的世界紀錄。

每到冬季東北季風來襲,台北東部山區恰好是迎風面,往往下起大雨;到了下午,太陽西移,台北西邊反而有陽光露臉──這時陽光射到水珠裡,經過兩次折射、一次反射,就會出現彩虹。

周昆炫說,其實這道彩虹由四層彩虹組成,除了比較明顯的「虹」跟以及虹的外圍、光度較弱與虹的顏色排列相反的「霓」外,還有因其大小及落入的位置不同所以較不易觀察到的二道「複虹」。 (自由時報)

DID YOU KNOW?

你知道嗎?

The rainbow is a natural phenomenon in which the sun’s rays are reflected and refracted by water droplets in the atmosphere. A secondary rainbow has one more reflection than the rainbow, with the color purple at the outer ring, in the reverse order in which it is manifest in the rainbow (with red outside the purple inside). It also has lower luminosity, and is usually less distinct.

虹是太陽光線被大氣中的水滴反射和折射而形成的一種自然現象。霓比虹多發生一次反射,其顏色為外紫內紅,與虹(外紅內紫)相反,光度亦較低,平時較不容易被觀測到。