The blooming season of cherry blossom trees across Japan has become earlier by an average 4.2 days over the past 50 years apparently due to global warming, a study by the Meteorological Agency has found.
The survey has also found that the blooming season for camellia trees got earlier by 9.4 days over the past half century, while gingko and maple trees start their leaf-shedding process much later than five decades ago.
The agency analyzed the data collected at its local meteorological observatories and weather stations across the nation between 1953 and 2004. As a result, the agency found that the blooming season of the four types of cherry blossoms -- hikanzakura, someiyoshino, ezoyamazakura and chishimazakura -- became earlier by an average of 4.2 days at 82 locations across the nation.
In big cities such as Tokyo and Nagoya, the blooming season for cherry blossoms got even earlier, by 6.1 days on average, apparently due to the "heat island phenomenon," while the blooming season became earlier by an average of 2.8 days in 11 small- and medium-sized cities such as Yamagata and Mito.
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