Tokyo — The blossoming of cherry trees (sakura), a symbol of the arrival of spring in Japan, attracts millions of visitors to the Asian country every year, however, Climate change is advancing its onset and heat waves put the opening of cocoons at risk.
This annual event, which dyes the entire country white and pink, traditionally occurred between the end of March – in the south of Japan – and the beginning of April – in the center – and even May – in the far north -, but the record temperatures They are advancing the beginning of flowering to February.
The average date when cherry trees begin to bloom has moved forward 1.2 days per decade since 1953as explained in a press conference by Daisuke Sasano, climate risk management official at the Japan Meteorological Agency (JMA).
Between 1961 and 1990, the average flowering date for Tokyo was March 29, while between 1991 and 2020, this figure has moved forward five days to March 24, notes the JMA expert.
In less urbanized areas of Japanlike Okinawa or Hokkaido, the advance payment has been somewhat smallerwith 3 days and 4 days respectively, so the expert considers that it is not only about climate change, but also about urbanization and the development of large cities.
“Last year was one of the earliest flowering years on record, with March 14, and this was a consequence of global warming combined with urbanization.”says Sasano.
For Kyoto, one of the most touristic cities in Japan and especially famous for its flowering, the JMA has collected data since the year 1400 – through writings of the time -, which show that at that time, the 'sakura' began around on April 11, while in recent decades it has been brought forward to mid-March.
A risk for the cocoons
Although there are varieties that flower earlier, such as 'kawazu', which opens its flowers in February, The JMA fears that an increase in temperatures may have an effect on the opening of the cocoons, which require cold for their formation.
“After blooming, the flowers disappear during the summer, a time when the buds form, which must be exposed to the cold winter or else they will not be able to bloom the next spring. There is a risk that the flower buds will go dormant if it is not cold enough.“, Add.
Although without wishing to conjecture on the matter, Sasano considers that some varieties of cherry trees, especially those from high mountains, They could experience difficulties in flowering if there is also an increase in temperature in these areas..
The expert also warns of delays in the color change of the autumn leaves (koyo), another symbol of the change of season in the Asian country and which occurs later and later each year with an average of 3 days delay per decade.
As with the 'sakura', this delay has been associated, among other factors, with the global increase in temperatures.
“'Sakura' is a turning point in the lives of many Japanese, as it coincides with entering university or starting new jobs.and there is a risk that this typical image of the time could be lost,” concludes the expert.
The cherry blossom is usually celebrated in Japan with the “hanami”a picnic among friends, family or co-workers, designed to enjoy the ephemeral beauty of the falling petals and which more and more foreigners join when they visit the Asian country.
In this way, the “sakura” has also become one of the main tourist attractions in Japan.. Some 63 million people traveled to and within Japan to see cherry trees, according to a 2019 estimate from the Japan National Tourism Organization (JNTO).