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The beginning of sakura has been creeping up on the Japanese in recent years. This year's start was eight days earlier than the average in Tokyo over the last half a century, part of a pattern that many scientists here attribute to global warming. Climate change "would contribute to the speeding up of the flowering," says Hiroshi Nagata, professor emeritus of Mie University who has been studying trees for 40 years and says the season is undeniably starting earlier.
Warmer temperatures are also changing the distribution of the species, he says, noting that the habitat of the somei yoshino species that is identified with cities such as Tokyo and Kyoto may be retreating northward, to the colder climate it needs to blossom.
For well over a millennium, the Japanese have made a sport of their collective anticipation of the annual explosion of pink and white sakura blossoms that marks the arrival of spring. The moment is more spiritual than botanical. The cherry blossom is a symbol of Japanese identity. The petal's 10-day span from glorious youth to wilting and inevitable death is seen as a metaphor for life's swift passage. It is also an excuse for executives, students and stay-at-home moms to ditch work and throw daylong parties of singing and drinking under canopies of petals.
The sakura once bloomed in a monthlong wave that spread northward, culminating on the chilly island of Hokkaido. Their progress was tracked, informally for centuries — and since 1953 by the scientists at the Japan Meteorological Agency — with a care and concern normally reserved for the movement of typhoons. But the official advent of sakura has moved up by 4.2 days since records started to be collected, Japan's Environmental Agency says. And the blossoms are coming out even earlier in the big cities, regardless of latitude: 6.1 days earlier in the six largest urban areas, according to the agency's data.
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http://www.latimes.com/news/printedition/asection/la-fg-cherries23mar23,1,5416851.story?coll=la-news-a_section