In Japan, cherry blossoms (or sakura in Japanese) are the epitome of spring. Hanami is known as the long standing tradition of welcoming spring1 as well as the annual appreciation of the fleeting beauty of nature. People congregate to enjoy festivities under the breath taking panorama of blooming flowers. Japanese citizens as well as tourists patiently wait to admire the beautiful flower trees that cascade the streets each year. Cherry blossom season typically begins in late March/early April, with the prime bloom only lasting up to a week.
In 1829 the peak blooming date was around April 18th. Since 1951, groups of meterologists and climatologists have been researching the advance of Japanese cherry tree blooming. According to two Japanese scientists, Yasuyuki Aono and Keiko Kazui, the full-blossom date for Kyoto’s cherry blossom trees can predict the March temperatures to within 0.1°C. The growth of cherry blossom trees is dependent on the weather in the months of February and March. As a result, the peak blooming date for cherry blossoms happens earlier in the year.
This phenomenon is not just occurring in Japan. The Japanese cherry blossom craze began in the US when the wife of the Japanese ambassador and First Lady Helen Herron Taft planted cherry tree seedlings from Japan on March 27th 1912. Since the National Cherry Blossom Festival launched in 1927, global warming has affected the blooming date in DC as well. Blooming now begins 5 days earlier than the original recorded date.
Every time I return home to Japan, I compare how warm it is compared to the previous year. However, I never think about the actual causes or the consequences of rising temperatures. Through data analysis by Yasyuki Aono, we are able to gain further insight into just how imminent the danger of climate change is in Japan. Aono estimates that temperatures have gone up at least 3.4°C (6.1°F) since 1820.
As seen by the graph above, Washington’s full bloom date has shifted five days earlier from the 6th of April to the 1st in between 1921 and 2017, whilst Kyoto’s from the 12th of April to the 5th. In Washington, D.C. as well as Kyoto, rising temperatures and earlier peak bloom dates are associated with the urban heat island (UHI) effect and growing concentrations of GHG. An urban heat island is a phenomenon in which urbanized areas may have higher temperatures than their surrounding rural landscapes. In an effort to mitigate this problem, the Diet of Japan has established the ‘Outline of the Policy Framework to Reduce UHI” in 2004, which imposes conditions such as annually monitoring measures in order to reduce temperatures in urban areas, as well as releasing a progress report to the public to diffuse the importance of the issue. 6The UHI measures also include the reduction of artificial heat emissions, avoiding the build up of heat by creating wind paths, promoting greening especially in urban farming, and improving pavement surfaces.7
The example of cherry blossom trees you gave very clearly shows how climate change can directly impact plant species. I wonder if this phenological shift has caused any trophic mismatch (etc. are there certain migrating bird populations that use the cherry blossoms for habitat? Do bugs rely on the blossoming of the trees for food or habitat?)
Your lens of cherry blossoms as an indicator of climate change is a unique take that I think provides a real visual of the effects of climate change. As the blossoming time becomes earlier it does show a quantitative change in their growth. The data that you present provides evidence on multiple levels of the impact of climate change. You include not only the data about the cherry blossoms, but general temperature changes and trends as well. Your multi-faceted process of presenting evidence is really great and helps to further your argument relating climate change in Japan to multiple factors and effects.
The effects of climate change can be seen on the scale of world-wide temperature phenomena, social and cultural traditions, and even individual plant species. Erin, your entry does a great job of highlighting the significance of the scope of climate change and its consequential effects – causing changes in practically every aspect of life. I appreciated your personal touch and observations that you gave to this piece, thus again, proving that the effects of climate change are indeed real as well as noticeable on an personal level.
Your use of the impact on one of the epitomes of nature’s beauty, sakura, is incredibly powerful to show the impact of climate change. Also, your graph is very illustrative of the shift in blooming date compared to Washington DC. I think it was a good idea to include a scientific figure, instead of the usual photograph.
I really enjoyed this post. I think your focus on the cherry blossoms is important and highlights not only an environmental issue, but how it is effecting the cultural traditions around the world. I think your application of UHI is interesting. How do you think climate change is effecting rural areas of Japan as well?
Erin your blog post was scientifically sound and eye opening. I live in Washington DC so I have also experienced this change first hand but it is nice to see some scientific data to support and demonstrate how climate change might be effecting specific blooms. Similar to Maggie I wonder what the effects of an earlier bloom could be. Or in general the effects of a shorter winter and longer months of hotter temperatures.
Erin, I love how your post touches on not only environmental impacts, but also the cultural ramifications of these changes. Nature is intertwined with many cultural values and through these events, the seriousness of our changing environment is illuminated. This phenomenon also reminds of how the farmers at McEnroe must also adjust their practices to adapt to the changing timeline of the seasons.
Thanks for sharing, Erin! While I was working on my research paper, I stumbled across some readings about plant-pollinator mismatch that can occur when the flowering date of a species moves up at a different sensitivity to the emergence of the plants’ pollinator. Do you know if this phenomenon is a concern for cherry blossoms? I ask because the window of opportunity for cherry blossoms is so short.
Cherry blossoms are a way to relate to the average citizen – often, those in higher academia and particularly scientific fields struggle to relate what their research means to individuals. without the direct link from scientist to person, misinformation can spread rapidly and has contributed immensely to climate change deniers. Like fireflies discussed in my post, things that are visually perceived are great tools for people to see it with their own eyes and no outside influence.
This is a fascinating way to explore the impacts of climate change- not only in one place, either, but globally. The data you presented was convincing and clear, and coupled with your personal anecdote this article really used multiple angles to prove your point. Has the progressively early blooming of cherry trees inspired any knowledge or action about climate change in Japan? Do many people associate the early warmth with climate change?