For a cloudy day in January, it is strikingly warm in Matsuyama city. Matsuyama is the largest city on Shikoku, Japan’s smallest main island. Usually the coldest month of the year, Matsuyama is today enjoying a very mild 14 degrees C.
The warmer winter days are only one sign of the increasing grasp of climate change in south Japan. Regional typhoon patterns are also changing, and the combination of rising temperatures and increasing typhoon damage poses new threats to the region.
According to the Japanese Meteorological survey, Average temperatures in Matsuyama have risen by 1.74 degrees C in the last century. The Paris agreement set an international target to limit the global temperature increase since pre-industrial times to 2 degrees C, and if possible to 1.5 degrees C. That means that Matsuyama has already missed the UN’s preferred target.
According to the Ehime prefectural office, The frequency of torrential rain, flooding, heat waves and drought have all increased in recent years. Ehime, one of four prefectures in Shikoku, has suffered damage to infrastructure and agriculture due to the increasingly extreme weather.
South Japan is no stranger to typhoons, but the storms are likely to become more dangerous as water temperatures continue to rise. Sato Yoshinobu, associate professor in the faculty of agriculture at Ehime University, says that rising sea water temperature has led to an increase in water vapour in the air, which is one of the main reasons for the heavy rain last year.
According to Sato, “The increase of sea surface temperature is mainly due to global warming.
According to the climate model simulation developed by the Japan Meteorological Agency (MRI-AGCM), the number of typhoons approaching Japan is predicted to decrease. However the strong typhoons will increase. The strong typhoons with strong wind and heavy rain will result in landslides and cause fruit to drop”
Climate change is already affecting the success of crop yields in Japan. A 2017 report from the Ministry of Agriculture, Forestry and Fisheries (MAFF) states that rice grains and fruit are failing to ripen completely. Popular fruits including grapes, apples and mandarin oranges are gradually losing their colour and the skins of the fruits are becoming softer.
Though the MAFF report shows that Japanese food production is already feeling the strain of climate change, Sato Yoshinobu believes that an average daily temperature of above 27 degrees C will result in very serious damage to both the local mandarin orange and rice crops, both of which are staples of the local economy. This past summer saw temperatures well over 30 degrees C, much higher than the temperature Sato considers serious for local crops.
Research stations in Shikoku are currently attempting adaption strategies to better cope with the new challenges to agriculture posed by regional climate change. For example, researchers are trying out delaying mandarin orange harvesting times and are breeding new varieties of rice better suited to the changing climate.
last year damage caused by typhoons and major storms increased considerably, and local residents were seriously affected. Takahashi Naoko, a teacher in Matsuyama, believes that the changing weather was particularly noticeable last year. “There was much more rain last year than before” she said. “In Ehime, the rain caused numerous landslides. It was very dangerous; the rivers overflowed, and sometimes roads were blocked by fallen trees or by the landslides. It really was a year of extremes”.
Most of the inhabited part of Ehime is by the coast, and the typhoons bring a hidden challenge to the region’s towns. The high winds bring salt spray far onto land, which then settles on agricultural plots. The accumulation of sea salt makes the land less productive, adding to the strain on crops already created by rising temperatures.
Not everyone is so concerned by changes in climate in Shikoku. Tanaka Hirohiko, long-term resident of Hojo in central Ehime, believes that the effects of climate change have been relatively slow in Shikoku and only poses a threat to the next generation.
Tanaka acknowledged however a number of noticeable changes. “The local fishing industry has been affected. I think that this is related to climate change, not overfishing”, he said. He is also concerned about local crops. “Because temperatures are higher now, there are more pests, which are damaging crops. This is damaging the local economy in general, as agriculture is such a major part of it”.
Tanaka also mentioned that a friend of his had completely lost his mandarin orange warehouse when it was swept away after a river burst its banks.
Shikoku is one of the most rural regions in Japan. Over 91% of Japan’s population lives in urban locations, but the cities in Shikoku are few and far smaller than those of the other three main islands of Japan. Because of this, the region is particularly sensitive to change in agriculture and damage to infrastructure between towns.