著者
Fumiaki Fujibe Jun Matsumoto
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.17, pp.220-223, 2021 (Released:2021-12-14)
参考文献数
24
被引用文献数
4

Using vital statistics data from 1995 to 2019, the relationships among interannual variations of total mortality, heat-stroke mortality, and temperature in summer were assessed in an attempt to estimate excess deaths in hot summer years in Japan. The number of deaths in July and August increased by 1.1% for each 1°C increment of summer mean temperature over Japan, with an eight-fold larger range of interannual variation than the more narrowly defined heat-stroke deaths. This fact implies that excess deaths due to heat are about eight times more prevalent than heat-stroke deaths and can be on the order of 10,000 in a hot summer year. Analyses by age group and cause of death indicated that excess deaths are largely associated with cardiovascular and respiratory diseases among elderly people.
著者
Fumiaki Fujibe
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.16, pp.175-179, 2020 (Released:2020-09-29)
参考文献数
21
被引用文献数
8

Japan underwent a nationwide self-restraint of human activities in spring 2020 to prevent the spread of the COVID-19 infection. In order to evaluate the effect of suppressed human activities on temperature in the Tokyo Metropolitan area, a statistical analysis was made for temperature anomalies during the self-restraint period using hourly data on the AMeDAS network. The temperature anomaly was defined by the departure from the value that would have been observed without self-restraint, estimated from regression analysis for temperatures at surrounding non-urban stations. It was found that the temperature in central Tokyo (Kitanomaru Park) had a negative anomaly of −0.49°C with a 95% confidence range of ±0.19°C on the average over the strong self-restraint period from April to May. The anomaly was larger in the nighttime than in the daytime, and was found in an area spreading for several tens of kilometers, with a decreasing magnitude according to the distance from Tokyo. These facts indicate a possibility that the reduction of anthropogenic heat release during the self-restraint period resulted in substantial decrease of temperature in the Tokyo Metropolitan area.
著者
Mariko Kumamoto Michiko Otsuka Takeshi Sakai Takashi Hamagami Hiroshi Kawamura Tadayoshi Aoshima Fumiaki Fujibe
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.9, pp.56-59, 2013 (Released:2013-05-04)
参考文献数
9
被引用文献数
6 9

A field experiment to clarify the characteristics of temperature distribution near an asphalt car road was carried out at the Meteorological Instruments Center in Tsukuba, Japan. Fifteen thermometers equipped with artificially ventilated radiation shields were installed on a wide grass field within a distance of 10 m from edges of the road. At a height of 0.5 m above the ground, the temperature on the leeward side of the road was found to show substantial bias from that on the windward side of the road. The biases were positive values of 0.2-0.4°C on the average and larger when the thermometers was nearer to the road or in cases of lower wind speed. The temporal variation of the biases showed a diurnal change and had a maximum peak in the evening and negative values during some hours of the day. Smaller positive biases around 0.1°C were also found at a height of 1.5 m during some time of the day whereas small negative biases were seen at a height of 2.5 m in summer. These results indicate complicated distribution of roadside temperature, although they can partly be interpreted by advection of air heated over the road.
著者
Fumiaki Fujibe Jun Matsumoto Hideto Suzuki
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.14, pp.144-147, 2018 (Released:2018-10-17)
参考文献数
14
被引用文献数
14

Relationships between daily heat-stroke mortality and temperature were statistically analyzed using Vital Statistics data for 1999 to 2016, with attention to regional differences related to different climate zones. An analysis based on data categorized for each prefecture has revealed that the daily heat-stroke mortality depends not only on daily temperature but also on the summer mean temperature in a way that a prefecture in a cooler summer climate tends to show a higher mortality for a specified value of daily temperature, implying the effect of acclimatization. Additionally, daily heat-stroke mortality is found to be higher for cases of higher temperature on preceding few days to a week, apparently due to accumulated heat stress, but is lower for cases of higher temperature a few weeks ago, presumably due to acclimatization. As for relative humidity, the mortality on a day of higher humidity tends to be higher for a specified value of daily maximum temperature, but lower for a specified value of daily mean temperature. It is also shown that heat-stroke mortality tends to be high on a day of low wind speed and long sunshine hours.
著者
Fumiaki Fujibe Jun Matsumoto
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
pp.2021-038, (Released:2021-10-13)
被引用文献数
4

Using vital statistics data from 1995 to 2019, the relationships among interannual variations of total mortality, heat-stroke mortality, and temperature in summer were assessed in an attempt to estimate excess deaths in hot summer years in Japan. The number of deaths in July and August increased by 1.1% for each 1°C increment of summer mean temperature over Japan, with an eight-fold larger range of interannual variation than the more narrowly defined heat-stroke deaths. This fact implies that excess deaths due to heat are about eight times more prevalent than heat-stroke deaths and can be on the order of 10,000 in a hot summer year. Analyses by age group and cause of death indicated that excess deaths are largely associated with cardiovascular and respiratory diseases among elderly people.
著者
Fumiaki Fujibe Nobuo Yamazaki Mitsugi Katsuyama Kenji Kobayashi
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.1, pp.41-44, 2005 (Released:2005-04-21)
参考文献数
14
被引用文献数
78 86

Long-term changes of precipitation intensity were analyzed using a dataset which was recently compiled by the Japan Meteorological Agency (JMA). After some quality check, data of four-hourly, daily, and hourly precipitation at 46, 61, and 8 stations, respectively, were used for the period 1898-2003 on the condition that data for at least 80 years were usable in each month. As the measure of precipitation intensity, ten categories were defined so as to equate the total precipitation amount in each month at each station. The result is characterized by increase of precipitation in high categories, namely intense precipitation, and decrease in low categories. The linear trend for the highest and lowest categories is ±20-30% per century. This feature is found invariably for four-hourly, daily, and hourly precipitation, and qualitatively for all the seasons and regions.
著者
Fumiaki Fujibe
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
pp.2020-030, (Released:2020-08-25)
被引用文献数
8

Japan underwent a nationwide self-restraint of human activities in spring 2020 to prevent the spread of the COVID-19 infection. In order to evaluate the effect of suppressed human activities on temperature in the Tokyo Metropolitan area, a statistical analysis was made for temperature anomalies during the self-restraint period using hourly data on the AMeDAS network. The temperature anomaly was defined by the departure from the value that would have been observed without self-restraint, estimated from regression analysis for temperatures at surrounding non-urban stations. It was found that the temperature in central Tokyo (Kitanomaru Park) had a negative anomaly of −0.49°C with a 95% confidence range of ±0.19°C on the average over the strong self-restraint period from April to May. The anomaly was larger in the nighttime than in the daytime, and was found in an area spreading for several tens of kilometers, with a decreasing magnitude according to the distance from Tokyo. These facts indicate a possibility that the reduction of anthropogenic heat release during the self-restraint period resulted in substantial decrease of temperature in the Tokyo Metropolitan area.
著者
Fumiaki Fujibe
出版者
(公社)日本気象学会
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.12, pp.106-110, 2016 (Released:2016-05-06)
参考文献数
22
被引用文献数
8

The annual variation of extreme precipitation in Japan was analyzed using hourly data at 981 stations for 36 years (1979-2014). Except over the Nansei Islands, the intensity of hourly extreme precipitation (Pext) defined by upper 0.1% cases is found to show a unimodal annual variation with a peak in midsummer, unlike total precipitation amount which has a bimodal annual variation with two peaks of Baiu and Shurin. The dependence of Pext on mean temperature is close to or slightly lower than the Clausius-Clapeyron (CC) rate of 6-7%/K, indicating that the annual variation of extreme precipitation is strongly linked to that of saturation vapor amount. On the other hand, Pext is different according to regions by several tens of percent for a fixed temperature. This fact suggests the influence of geographical factors on its spatial distribution. As for 24-hour precipitation, Pext shows larger deviation from the CC scaling and larger regional differences than that of hourly precipitation, implying stronger control of synoptic effects in generating long-lasting heavy rainfall.
著者
Fumiaki FUJIBE Nobuo YAMAZAKI Kenji KOBAYASHI
出版者
Meteorological Society of Japan
雑誌
気象集誌. 第2輯 (ISSN:00261165)
巻号頁・発行日
vol.84, no.6, pp.1033-1046, 2006 (Released:2007-01-22)
参考文献数
26
被引用文献数
43 59

Long-term changes in the intensity and frequency of heavy precipitation in Japan were analyzed using quality checked daily precipitation data at 51 stations from 1901 to 2004. The analysis is based on ten categories defined from precipitation intensity and frequency, and some indices of heavy precipitation, such as ≥100 mm days, the annual maximum, and the top 100 cases during the 104 years. The result indicates that heavy precipitation based on these indices has increased during the 104 years. The linear trend of precipitation corresponding to the upper 10% is 2.3% per decade, and that of the number of top 100 cases is 2.6% per decade on the average over the stations. The increase is most pronounced in western Japan and in autumn, while weak, but similar signals are found in other regions and seasons as well. However, no increasing trend is found for less intense precipitation, such as ≥50 mm days and the number of top 1000 cases.Analysis was also made for 5, 11, and 31 day precipitations, and some indices of dry weather. It is found that the frequency of dry weather has increased during the 104 years. The number of days with precipitation less than 1 mm has increased in all the seasons and regions, with a trend of 0.4-0.7% per decade on the average, while the lower 1% ofcases of 31-day precipitation have doubled with a trend of 10% per decade.
著者
Junya Miyajima Fumiaki Fujibe
出版者
(公社)日本気象学会
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.7, pp.157-160, 2011 (Released:2011-10-14)
参考文献数
6
被引用文献数
5 9

Climatological features of the distribution of extreme precipitation in Japan were documented using record values of ten-minute, hourly and daily precipitation for 1994 to 2009. It was found that the distribution of top ten-minute precipitation has a moderate north-south gradient (increasing southward at about 3% per degree in latitude), while ten-minute precipitation of lower ranks (up to 50th to 100th cases at each station) shows a stronger latitude dependence (about 6% per degree) that is comparable to those of hourly and daily precipitations. In addition, extreme precipitation shows local maxima on southern sides of land in western Japan corresponding to orographic enhancement, which is found for all the time scales but is most conspicuous for daily precipitation.
著者
Fumiaki Fujibe
出版者
(公社)日本気象学会
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.11, pp.5-9, 2015 (Released:2015-01-30)
参考文献数
14
被引用文献数
1 26

Long-term changes in extreme hourly precipitation in Japan were examined using data at 983 stations for 1979 to 2013, with relation to the variations in air temperature (AT) and sea-surface temperature (SST). According to the statistics over the whole country, annual maximum and 95 percentile precipitations show increasing trends of 2-4%/decade, whereas AT and SST have risen at a rate of 0.2-0.3°C/decade. Analysis for each region and season indicates that the increase in extreme precipitation is a nation-wide feature and is not limited to a single season. Moreover, year-to-year variations in extreme precipitation tend to be in phase with those of AT and SST, with a correlation coefficient of 0.5-0.6 on the annual basis, although negative correlation is found for the summer season in western Japan and the Nansei Islands.
著者
Kyosuke Ishii Syugo Hayashi Fumiaki Fujibe
出版者
日本大気電気学会
雑誌
Journal of Atmospheric Electricity (ISSN:09192050)
巻号頁・発行日
vol.34, no.2, pp.79-86, 2014 (Released:2014-08-28)
参考文献数
24
被引用文献数
2 20

The temporal and spatial distributions of cloud-to-ground (CG) lightning in and around Japan were examined for a seven-year period (2002?2008) by using lightning location data from the Lightning Detection Network System operated by the Japan Meteorological Agency. The frequency of CG flashes was found to be high over land area in summer. During winter, many CG flashes were located along the coast of the Sea of Japan of central Honshu (Hokuriku area) and off the coast of the Pacific side (Kanto-Tokai area). A detailed analysis of the Hokuriku and Kanto-Tokai areas revealed diurnal variations characterized by a peak in the afternoon for inland areas, and a peak in early morning for coastal and offshore areas of the Hokuriku area in summer. For winter, the diurnal variation of CG flash density is indistinct in the Hokuriku region, where CG flashes are strongly concentrated within 20 km from the coastline, whereas it has a maximum in the early morning off the coast of the Kanto-Tokai area.