Like most of the rest of the world, Japan has been slowly warming for the last century or so. So that could have some effect on cherry blossoming. Pretending that global warming is the only infulence or even the major influence is however slipshod.
The obvious influence is urbanization. Urban centres are warmer and that is even more so as society becomes ever more energy intensive. The more people use air-conditioners in summer and heaters in winter the greater will be the heat output into the urban environment. Much warmer cities rather than the trivial increase in global warming would be the major influence on cherry blossoming
About 63 million people in a normal year flock to Japan to see its most famous flower in full bloom.
Cherry blossoms, or sakura, hit their peak bloom in April, when they paint the country’s parks and gardens with shades of pink and white and fuel a multimillion spring tourism boom.
But this year, in the ancient capital city of Kyoto, the cherry blossoms hit peak bloom too early, on March 26 – the earliest since the Japan Meteorological Agency began collecting data on the flowers 70 years ago.
Others say the bloom is even earlier than what’s been noted in diaries and poetry from Kyoto that date back hundreds of years, AP reported.
According to the 2021 data in Kyoto, the cherry blossoms reached peak bloom 10 days ahead of the 30-year average, and it was a similar story in other cities across Japan.
Scientists fear climate change is to blame.
“We can say it’s most likely because of the impact of the global warming,” Shunji Anbe from the Japan Meteorological Agency told AP, adding the trees were sensitive to temperature changes.
The average March temperature in Kyoto, a key destination for cherry blossoms, rose to 10.6C in 2020, up from 8.6C in 1953. This March, the average temperature was even higher, at 12.4C.
Of the 58 benchmark trees across Japan that are tracked by the agency, 40 reached their peak bloom before the start of April, with 14 blooming in record time, according to AP.
It normally takes about two weeks for the first bud to appear and all the blossoms to fall from the tree.
Benjamin Cook, a research scientist at Columbia University, told The Washington Post the cherry blossom peak bloom date had been relatively stable for about 1000 years, from the years 812 to 1800, before a sharp shift to earlier in spring.
“Since the 1800s, warming has led to a steady trend toward earlier flowering that continues to the present day,” he said.
“Some of this warming is due to climate change, but some is also likely from an enhanced heat island effect due to increased urbanisation of the environment over the last couple of centuries.”