著者

Hirotaka Kamahori Osamu Arakawa

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.14, pp.165-169, 2018 (Released:2018-11-09)

参考文献数

18

被引用文献数

2 10

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Tropical cyclone (TC) induced precipitation (TCP) over Japan is evaluated with the rain gauge observation based gridded dataset APHRO_JP. The TC–influenced frequency reaches a maximum in the Nansei Islands and decreases monotonically with latitude. On the other hand, the distribution of TCP indicates different characteristics from the one of TC–influenced frequency. The largest annual TCP, 500 mm yr−1 or more, occurs over eastern Kyushu (E-Kyushu), southern Shikoku (S-Shikoku), and the eastern Kii peninsula (E-Kii), where it accounts for 15% or more of the total precipitation. The maximum daily TCP amounts to 200 mm d−1 in those three areas, which are all located on the eastern side of Japan and correspond to eastward or southeastward topographic inclines. A significant relationship is found between the amount of annual TCP and topographic incline, and the large amount of TCP concentrates in the eastward or the southeastward inclines. The extreme daily TCP once every 50 years is also evaluated. The extreme daily TCP is estimated to be 500 mm d−1 comparable to the climatological annual TCP in E-Kyushu, S-Shikoku, and E-Kii. These three areas appear to be the most hazardous part of Japan in terms of TCP.

著者

Tetsuya Takemi Rui Ito Osamu Arakawa

出版者

Japan Society of Hydrology and Water Resources (JSHWR) / Japanese Association of Groundwater Hydrology (JAGH) / Japanese Association of Hydrological Sciences (JAHS) / Japanese Society of Physical Hydrology (JSPH)

雑誌

Hydrological Research Letters (ISSN:18823416)

巻号頁・発行日

vol.10, no.3, pp.81-87, 2016 (Released:2016-11-12)

参考文献数

23

被引用文献数

7 19

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Typhoon Mireille (1991) caused devastation over Japan. Assessing the impacts of such an extreme typhoon under global warming is an important task to prevent and mitigate future natural disasters. This study investigated the influences of global warming on the strong winds of Typhoon Mireille by conducting pseudo-global warming (PGW) experiments with a regional model. Since significant damages to forest areas occurred in Kyushu and Tohoku, we compared the typhoon impacts in these two regions. It was demonstrated that on average the mean wind speeds induced by Typhoon Mireille become stronger in Kyushu and weaker in Tohoku under the PGW conditions than under the September 1991 conditions. The difference between the two regions in the future is due to the simulated typhoons under PGW being stronger at lower latitudes and weakening more rapidly at higher latitudes. Thus, the impacts of Typhoon Mireille under a warmed climate are considered to be more severe at a lower latitude and weaker at a higher latitude.

著者

Hideo Shiogama Yukiko Imada Masato Mori Ryo Mizuta Dáithí Stone Kohei Yoshida Osamu Arakawa Mikiko Ikeda Chiharu Takahashi Miki Arai Masayoshi Ishii Masahiro Watanabe Masahide Kimoto

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.225-231, 2016 (Released:2016-08-07)

参考文献数

37

被引用文献数

4 25

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We describe two unprecedented large (100-member), long-term (61-year) ensembles based on MRI-AGCM3.2, which were driven by historical and non-warming climate forcing. These ensembles comprise the “Database for Policy Decision making for Future climate change (d4PDF)”. We compare these ensembles to large ensembles based on another climate model, as well as to observed data, to investigate the influence of anthropogenic activities on historical changes in the numbers of record-breaking events, including: the annual coldest daily minimum temperature (TNn), the annual warmest daily maximum temperature (TXx) and the annual most intense daily precipitation event (Rx1day). These two climate model ensembles indicate that human activity has already had statistically significant impacts on the number of record-breaking extreme events worldwide mainly in the Northern Hemisphere land. Specifically, human activities have altered the likelihood that a wider area globally would suffer record-breaking TNn, TXx and Rx1day events than that observed over the 2001-2010 period by a factor of at least 0.6, 5.4 and 1.3, respectively. However, we also find that the estimated spatial patterns and amplitudes of anthropogenic impacts on the probabilities of record-breaking events are sensitive to the climate model and/or natural-world boundary conditions used in the attribution studies.

著者

Rui Ito Tetsuya Takemi Osamu Arakawa

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.100-105, 2016 (Released:2016-04-22)

参考文献数

23

被引用文献数

5 38

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Typhoon Songda (2004), while undergoing an extratropical transition and reintensification over the Sea of Japan, spawned serious damages over forest areas in the northern part of Japan. To clarify influences of anticipated global warming on the typhoon hazard in high-latitude regions, we carried out numerical experiments on Typhoon Songda in a current climate and a pseudo global warming climate and examined the impacts of climate change on the typhoon intensify and windstorms for the region. The typhoon intensity at its maturity becomes stronger in a warming climate, and the typhoon while passing over the Sea of Japan weakens more rapidly in the warming climate. Thus the strong wind over the northern part of Japan in the warming climate also becomes weaker. We examined atmospheric environmental factors in the higher-latitude region: sea surface temperature, vertical shear, and meridional gradient of temperature. It was found that the environmental meridional gradient of temperature at the 500 hPa level is smaller in the warming climate than in the current climate, which indicates that the baroclinicity becomes weak under global warming. The weak baroclinicity makes the typhoon environment unfavorable for the extratropical transition, and therefore, possibly reduces the severity of typhoon wind in northern Japan.

著者

Ryo Mizuta Osamu Arakawa Tomoaki Ose Shoji Kusunoki Hirokazu Endo Akio Kitoh

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.10, pp.167-171, 2014 (Released:2014-10-23)

参考文献数

14

被引用文献数

83 140

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Climate changes for the end of the 21st century projected by Coupled Model Intercomparison Project phase 5 (CMIP5) models are classified into three clusters by a cluster analysis of annual-mean tropical sea surface temperature (SST) change patterns. The classified SST change patterns are featured by the zonal gradient of the change in the equatorial Pacific and inter-hemispheric contrast of the warming. Precipitation and atmospheric circulation responses are composited for the clusters, and their relationships to the SST changes are examined. Precipitation increase is larger where SST warming is larger than surroundings and vice versa. Common precipitation and atmospheric circulation responses for each cluster are found also over tropical lands and the extratropics as well as in the tropical oceans, suggesting that some remote effects of the tropical SST change patterns could be one reason for less agreement among CMIP5 models in climate changes.