The flowers, which experience a “peak bloom” that lasts only a few days, have been revered in Japan for more than a thousand years. Crowds celebrate with viewing parties, come to the most popular places to take photos and have picnics under the branches.
But this year, cherry blossom season has arrived and gone in a blink of an eye, one of the earliest blooms on record – and scientists warn that it is a symptom of a large climate crisis that threatens ecosystems everywhere is.
And in the capital Tokyo, Cherry Blossom reached full bloom on March 22, the second-oldest date on record.
“As global temperatures warm, past spring frosts are occurring earlier and flowering is happening sooner,” Dr. Louise Ziska told Columbia University Environmental Health Sciences.
The peak bloom dates change every year, depending on a number of factors, including weather and rainfall, but a general trend of earlier and earlier increases has been shown. In Kyoto, the peak date, according to Aono figures, hovered for centuries in the middle of April, but began to move into the early April during the 1800s. The date is only steeped a handful of times in recorded history at the end of March.
“Sakura blooms are very temperature sensitive,” Aono said. “Flowers and full bloom can occur before or after depending on temperature alone,” he said. “The temperature was low in the 1820s, but it has risen to about 3.5 ° C (6.3 ° F) to date.”
This year’s season in particular affected the bloom dates, he said. The winter was very cold, but the spring heats up rapidly and unusually, so “the buds are fully awake after sufficient rest.”
However, their early blossom is the tip of the iceberg spreading across the world, which can destabilize the natural systems and economies of countries, said Amos Tai, assistant professor of earth sciences at the Chinese University of Hong Kong.
There are two sources of increased heat, which are the main factors that cause flowers to bloom first: urbanization and climate change. With increasing urbanization, cities become warmer than the surrounding rural area, known as the heat island effect. But one major reason is climate change, which has caused rising temperatures throughout the region and the world.
And while these are not earlier dates, it is a case for tourists to see the peak bloom before the petals fall – it can have a lasting effect on the entire ecosystem, and threaten the survival of many species.
For every action there is a reaction
Tai said that plants and insects rely heavily on each other, and both use environmental signals “to regulate the timing of different stages of their life cycle”. For example, plants feel the temperature around them and if it is warm enough for a sustained period, they begin to thrive and their leaves begin to grow. Similarly, insects and other animals depend on temperature for their life cycle, meaning high heat can cause rapid growth.
Tai said, “Relationships between plants and insects and other organisms have evolved over many years – thousands to millions of years.” “But in the recent century, climate change is really ruining everything and spoiling all these relationships.”
Different plants and insects can respond to increased heat at different locations, throwing their life cycle out of the sink. Whereas they once scheduled their growth time together each spring, now the flowers can bloom before the insects are ready, and vice versa – meaning “insects cannot get enough food to eat from the plants, and the plants.” There are not enough pollinators (reproduce), ”he said.
“Ecosystems are not accustomed to these types of large fluctuations, it causes them a lot of stress,” Tai said. “Productivity may decrease, and the ecosystem may collapse in the future as well.”
Not limited to cherry blossoms
And the effects of climate change are not limited to cherry blossoms alone. “Cherry blossoms catch the eye, people like to go to see them, but a lot of other plants are also experiencing changes in their life cycle, and can have an even greater impact. On the sustainability of their ecosystems , “Tai said.
In some areas, farmers may be forced to change the type of crops they grow. Some climates will be very hot that they are growing right now, while other climates will see more flooding, more snow, more moisture in the air, which can be grown.
Tai said, “(farmers) have a very difficult time predicting when their year will be good, when their year will be bad.” “Agriculture is like a gamble now, because climate change is randomizing the things happening in our ecosystem.”