Cherry blossom front explained

The is the advance of the cherry blossoms across Japan. The Japan Meteorological Agency records the opening and full bloom of the blossoms from Kyūshū in late March to Hokkaidō in the middle of May. The advancing front is also the subject of regular reports by the major news agencies. The cherry blossom is of great public interest in Japan due to its symbolism and the custom of flower viewing known as hanami.

Forecasts

From 1951 the Japan Meteorological Agency produced forecasts for the Kantō region and from 1955 for the whole of Japan excepting Okinawa and the Amami Islands.^[1] From 2010, the Agency left forecasting to the private sector although it continues to observe and determine the impact of the climate upon the flowering of the cherry.^{[2] [3]} The forecast is based on the Arrhenius equation, with the formula$$\backslash text\; =\; \backslash exp\backslash left[9.5\; \backslash times\; 10^3\; \backslash cdot\; \backslash frac\{T\; -\; 288.2\}\{288.2\backslash ,T\}\backslash right],$$where T is the mean day temperature in kelvins, and DTS represents the number of days transformed to standard temperature.^{[4] [5] [6]}

Blossoming

The day of opening^[7] is defined as the point at which at least five to six flowers have opened on the sample tree. The day of full bloom is when at least 80% of the flowers have opened. The Yoshino cherry is typically observed since, from the late Edo period, it has been planted across the archipelago.^[8] Sample trees also include the Higan cherry in the south and Prunus sargentii (Sargent's cherry) in the north.^[8]

In 2006 it was reported that the cherry blossoms might overtake the plum blossoms before reaching Hokkaidō.^[9]

Sample trees

There are fifty-nine sample trees at any one time. Successor junior trees are selected from among prospective candidates when an incumbent becomes too old or is otherwise incapacitated.^[3] For instance, the sample tree in Mito collapsed under the weight of snow in 2005, while that at the southern tip of Ishigaki Island was felled by a typhoon a year later.^[3] The fifty-nine sample trees are located across Japan, corresponding to the sites of the Agency's principal weather stations:^{[10] [11] [12]}

• Okinawa: Ishigaki, Miyako-jima, Naha, Minamidaitō
• Kyūshū/Yamaguchi: Fukuoka, Shimonoseki, Ōita, Nagasaki, Saga, Kumamoto, Miyazaki, Kagoshima, Amami (formerly Naze)
• Shikoku: Takamatsu, Tokushima, Matsuyama, Kōchi
• Chūgoku: Hiroshima, Okayama, Matsue, Tottori
• Kinki: Ōsaka, Hikone, Kyōto, Maizuru, Kobe, Nara, Wakayama
• Tōkai: Nagoya, Shizuoka, Gifu, Tsu
• Kantō: Tōkyō, Mito, Utsunomiya, Maebashi, Kumagaya, Chōshi, Yokohama, Nagano, Kōfu
• Hokuriku: Niigata, Toyama, Kanazawa, Fukui
• Tōhoku: Sendai, Aomori, Akita, Morioka, Yamagata, Fukushima
• Hokkaidō: Sapporo, Wakkanai, Asahikawa, Abashiri, Obihiro, Kushiro, Muroran, Hakodate.

See also

• Leaf peeping
• Ueno Park

External links

• 2012 day of opening (JMA record)
• 2012 day of full bloom (JMA record)
• 2011 day of opening (JMA record)
• 2011 day of full bloom (JMA record)
• JMA flowering data, 1953–2010

Notes and References

1. Web site: 新しいサクラの開花予想 . . 1 March 2012 . dead . https://web.archive.org/web/20130106160101/http://www.data.jma.go.jp/sakura/data/cb/kaisetu24sakura.pdf . 6 January 2013 .
2. Web site: 気象庁におけるさくらの開花予想の発表終了について . . 25 December 2009 . 1 March 2012.
3. News: 桜の標本木、進む代替わり 老齢化で後進育成急ピッチ . 25 March 2011 . 1 March 2012 . Asahi Shimbun.
4. Web site: さくら開花予想方法について . . 1 March 2012 . dead . https://web.archive.org/web/20120506135823/http://www.data.jma.go.jp/sakura/data/cb/sakura.html . 6 May 2012 .
5. Climatological Studies on Blooming of Cherry Tree (Prunus yedoensis) by Means of DTS Method . Japanese, English . Aono Yasuyuki . Bulletin of the University of Osaka Prefecture. Ser. B, Agriculture and Life Sciences . 1993 . 45 . 155–92 . Osaka Prefecture University.
6. Web site: Predicting Peak Bloom Date of Cherry Blossoms: Finding an Optimal Heuristic . Dass, Vidhya . Brennan, Elizabeth . . 9 March 2012 . dead . https://www.webcitation.org/6HTWixRvF?url=http://filebox.vt.edu/users/ebren83/ai/final.doc . 18 June 2013 .
7. [Japanese language|Japanese terms]
8. Web site: さくらの開花日と満開日 . . 1 March 2012.
9. News: Cherries winning the blossom race . Joyce, Colin . 7 April 2006 . 1 March 2012 . The Daily Telegraph.
10. Web site: Cherry blossoms 2012 - day of opening . Japanese . . 1 March 2012 . dead . https://web.archive.org/web/20120308233449/http://www.data.jma.go.jp/sakura/data/sakura2012_kaika.html . 8 March 2012 .
11. Web site: Agency Weather Stations (気象台, 測候所) . . 2 March 2012 . Japanese.
12. Web site: 2009 revised forecast (Note 4. 気象台や測候所の定めた標本木) . . 2 March 2012 . Japanese . dead . https://web.archive.org/web/20120420192028/http://www.jma-net.go.jp/nagoya/hp/asl/oshirase/oshirase_090318.pdf . 20 April 2012 .