Weathernews announced the national "Sugi cypress pollen" trend during the 2016 pollen season. The amount of pollen scattered in 2016 is expected to be 30% less than normal due to the short hot season this summer. During the pollen season, the air purifier filters in the room can be surprisingly dyed yellow or white, but the 2016 season may be a little better.

■ Trends in pollen dispersal next spring
The amount of pollen scattered in the Sugi and Hinoki pollen season in 2016 is expected to be less than normal (2008-2015 average) nationwide, and there are conspicuous areas where the expected amount of scattered is less than 70% of normal, especially in eastern Japan. Even in Yamagata and Iwate prefectures, where the average rate exceeds 90%, it is expected that more pollen than normal will not fly.


Compared to the 2015 season, there are areas where the amount of pollen scattered in 2015 was less than 100% compared to the previous year, centering on western Japan, but the amount is likely to be about the same as normal to less.


◆ The summer of 2015 was unsuitable for the growth of male flowers due to lack of sunshine and low temperature in the latter half of August. The production of male flowers, which is the source of stamens, tends to increase.

However, in the summer of 2015, although the hot days were concentrated in early August, the temperature in late August was much lower than normal in eastern Japan. In Tokyo, there are 6 days when the maximum temperature in August does not reach 25 degrees Celsius, which is the record since 1993, when it was a cold summer. Even in western Japan, the temperature in late August is much lower than normal, so this summer has less sunshine than normal, and it can be said that the weather was not suitable for the growth of male flowers, mainly in eastern and western Japan.


◆ In Tohoku and eastern Japan, there are few pollen in the "back year", and in western Japan, there is a lot of pollen in the "front year ". The year following the "front year" tends to be the "back year" when the amount of scattering decreases. Since 2015 was the "back year" in Hokkaido and western Japan, 2016 will be the "front year", and the amount of pollen scattered is expected to increase from 2015. On the other hand, in Tohoku and eastern Japan, 2015 was the "front year", so 2016 is the "back year", and the amount of scattering tends to be smaller than the previous year on a periodic basis.

■ By area: Pollen scattering forecast ◆ Hokkaido (* birch pollen)
The amount of pollen scattered is determined by the summer weather of the previous year and the increasing / decreasing trend depending on the "front year" and "back year". 2015 was the “back year” and the amount of scattering was very small, but 2016 will be the “front year” and the amount of scattering is likely to increase from the previous year.


Although there were more sunny days in the summer of 2015 than in the previous year, the hours of sunshine were less than in normal years. The amount of birch pollen scattered in the 2016 season is expected to be about 70% of the average year. However, it will increase by about 50% compared to the 2015 season when the number of scattering was very small, so we cannot be alert.


◆ Northern Tohoku
In the summer of 2015, the area on the Pacific side was more sunshine, and the weather was such that the growth of male Sugi flowers was promoted. However, 2016 will be a “back year” and the number of scattering will tend to be smaller than the previous year.


Due to summer weather and biennial fluctuation trends, the expected amount of scattering in the 2016 season is expected to be about 80 to 90% of the average year and 70 to 90% of the 2015 season. In the northern part of Tohoku, cedar pollen is scattered a lot in spring, and cypress pollen is hardly scattered.


◆ Southern Tohoku
In the summer of 2015, there were sunny and hot days in the area on the Pacific side, and the weather was such that the growth of male Sugi flowers was promoted. However, 2016 will be a “back year” and the number of scattering will tend to be smaller than the previous year.


Due to summer weather and biennial fluctuations, the expected amount of scattering in the 2016 season is expected to be 60-100% of the normal and 2015 seasons. In the southern part of Tohoku, cedar pollen is scattered a lot in spring, and cypress pollen is hardly scattered.


◆ Kanto
In the summer of 2015, clouds are more likely to spread in the southern part than in the summer of 2013 and 2014, and after the latter half of August, the temperature is lower than normal, making the weather somewhat unsuitable for the growth of male flowers of Japanese cypress and cypress. rice field. In addition, 2016 will be the “back year”, and the number of scattering is likely to be smaller than the previous year.


Due to summer weather and biennial fluctuations, the expected amount of scattering in the 2016 season is expected to be 40-70% in the normal year and 60-90% in the 2015 season.


◆ Hokuriku / Northern Koshin (Nagano Prefecture)
Compared to 2014, the summer of 2015 was sunny and hot, mainly in Niigata and Nagano prefectures, and the weather encouraged the growth of male flowers of Sugi and Hinoki. However, 2016 is the “back year” and the number of scattering is likely to be smaller than the previous year.


Due to summer weather and biennial fluctuations, the expected amount of scattering in the 2016 season is expected to be 60-90% of the average year. Compared to the 2015 season, it is expected to be about 70-80% in Niigata and Nagano prefectures, and 100-110% in other regions. In Hokuriku, cedar pollen is mainly scattered in spring, and cypress pollen tends to be low.


◆ Tokai / Southern Koshin (Yamanashi Prefecture)
In the summer of 2015, there were sunny and hot days mainly in Gifu and Mie prefectures, and the weather was more stimulating for the growth of male flowers of Sugi and Hinoki than in the summer of 2014. However, 2016 is the “back year” and the number of scattering is likely to be smaller than the previous year. On the other hand, in Mie and Gifu prefectures, there was little scattering in 2015, so it is expected that there will be more scattering than in the previous year.


Due to the summer weather and the trend of increase and decrease every other year, the expected amount of scattering in the 2016 season is expected to be as small as 50-80% in the average year, but compared to the 2015 season, it is 200% in Mie prefecture and 150% in Gifu prefecture, which is the same as the previous year. It is expected to exceed. In Shizuoka, Aichi, and Yamanashi prefectures, the ratio is expected to be as low as 50-70% compared to 2015.


◆ Kinki
2016 is a “table year” and the number of scattered cypresses tends to increase from the previous year, but the summer sunshine in 2015 increased from 2014 but not enough, and it is a little unsuitable for the growth of male flowers of Sugi and Hinoki. It was a nice weather.


Due to summer weather and biennial fluctuation trends, the expected amount of scattering in the 2016 season is expected to be 60 to 90% of the average year. In addition, compared to the 2015 season when the amount of scattering was small, it is expected to be 180-200% in Nara and Wakayama prefectures, and 120-130% in other prefectures.


◆ Sanin
2016 is a “table year” and the number of scattered cypresses tends to increase from the previous year, but the summer sunshine in 2015 increased from 2014 but not enough, and it is a little unsuitable for the growth of male flowers of Sugi and Hinoki. It was a nice weather.


Due to summer weather and biennial fluctuations, the expected amount of scattering in the 2016 season is expected to be 50-70% in the normal year and 120-160% in the 2015 season. The amount of scattering is less than normal, but it is expected to exceed the previous season.


◆ Sanyo
2016 will be the “table year” and the number of scattering will tend to increase from the previous year, but in 2015, the rainy season was longer than normal, and the hot and sunny days did not last much in summer, so Sugi and Hinoki The weather was unsuitable for the growth of male flowers.


Due to summer weather and biennial fluctuation trends, the expected amount of scattering in the 2016 season is expected to be about 80% of the average year, and 110 to 130% in the 2015 season.


◆ Shikoku
2016 will be the “table year” and the number of scattering will tend to increase from the previous year, but in 2015, the rainy season was longer than normal, and the hot and sunny days did not last much in summer, so Sugi and Hinoki The weather was unsuitable for the growth of male flowers.


Due to summer weather and biennial fluctuations, the expected amount of scattering in the 2016 season is expected to be 50-90% in the normal year and 150-210% in the 2015 season.


◆ Northern Kyushu
In northern Kyushu, "front year" and "back year" tend not to appear clearly, and it is thought that summer weather greatly affects the growth of male flowers of Sugi and Hinoki. In 2015, the rainy season was longer than normal, and the hot and sunny days did not last much in summer, making the weather unsuitable for the growth of male flowers of Sugi and Hinoki.


The expected amount of scattering for the 2016 season is expected to be 40-80% of the average. However, since the amount of scattering in the 2015 season was very small, many prefectures are expected to exceed 200% compared to 2015.


◆ Southern Kyushu
In southern Kyushu, "front year" and "back year" tend not to appear clearly, and it is thought that summer weather greatly affects the growth of male flowers of Sugi and Hinoki. In 2015, there were sunny and hot days immediately after the end of the rainy season, but there was not enough sunshine in the summer, making it unsuitable for the growth of male flowers.


The expected amount of scattering in the 2016 season is expected to be about 40% of the average in Kagoshima prefecture and about 70% of the average in Miyazaki prefecture. However, due to the increase in sunshine this summer compared to 2014, it is expected to be around 100-120% in 2015.