著者

Kosuke Ito Hiroyuki Yamada Munehiko Yamaguchi Tetsuo Nakazawa Norio Nagahama Kensaku Shimizu Tadayasu Ohigashi Taro Shinoda Kazuhisa Tsuboki

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.14, pp.105-110, 2018 (Released:2018-07-28)

参考文献数

30

被引用文献数

1 23

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The inner core of Tropical Cyclone Lan was observed on 21-22 October 2017 by GPS dropsondes during the first aircraft missions of the Tropical Cyclones-Pacific Asian Research Campaign for the Improvement of Intensity Estimations/Forecasts (T-PARCII). To evaluate the impact of dropsondes on forecast skill, 12 36-h forecasts were conducted using a Japan Meteorological Agency non-hydrostatic model (JMA-NHM) with a JMA-NHM-based mesoscale four-dimensional data assimilation (DA) system. Track forecast skill improved over all forecast times with the assimilation of the dropsonde data. The improvement rate was 8-16% for 27-36-h forecasts. Minimum sea level pressure (Pmin) forecasts were generally degenerated (improved) for relatively short-term (long-term) forecasts by adding the dropsonde data, and maximum wind speed (Vmax) forecasts were degenerated. Some of the changes in the track and Vmax forecasts were statistically significant at the 95% confidence level. It is notable that the dropsonde-derived estimate of Pmin was closer to the real-time analysis by the Regional Specialized Meteorological Center (RSMC) Tokyo than the RSMC Tokyo best track analysis. The degeneration in intensity forecast skill due to uncertainties in the best track data is discussed.

著者

Narihiro Orikasa Masataka Murakami Takuya Tajiri Yuji Zaizen Taro Shinoda

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.16, pp.185-191, 2020 (Released:2020-10-17)

参考文献数

22

被引用文献数

2

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Aircraft observations were conducted over the eastern mountainous areas of the United Arab Emirates (UAE) in September 2017 to characterize the microphysical properties of diurnal convective clouds. Aerosol particle and cloud condensation nuclei (CCN) measurements indicate that the air mass had a continental nature, resulting in high cloud droplet concentrations of 600-800 cm−3. Two case studies were undertaken to obtain the vertical profiles of hydrometeors up to the cloud top. The ice particle number concentrations in the updraft core were a few particles L−1, which is similar to the primary ice nucleating particle (INP) number concentrations estimated from immersion freezing of high concentration dust particles in the convectively mixed boundary layer. The ice particle number concentrations were several tens of particles L−1 outside the updraft core in the upper levels. INP measurements and the observed cloud microphysical structure suggest that drizzles, frozen via the immersion freezing nucleation of dust particles, formed graupel embryos and ice particles, with concentrations of one to two orders of magnitude greater than those of the primary INPs, which may be generated via secondary ice production and/or ice particle accumulation from primary ice nucleation in clouds with relatively warm cloud top temperatures (approximately −12°C).

著者

Narihiro Orikasa Masataka Murakami Takuya Tajiri Yuji Zaizen Taro Shinoda

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

pp.2020-032, (Released:2020-08-28)

被引用文献数

2

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Aircraft observations were conducted over the eastern mountainous areas of the United Arab Emirates (UAE) in September 2017 to characterize the microphysical properties of diurnal convective clouds. Aerosol particle and cloud condensation nuclei (CCN) measurements indicate that the air mass had a continental nature, resulting in high cloud droplet concentrations of 600-800 cm−3. Two case studies were undertaken to obtain the vertical profiles of hydrometeors up to the cloud top. The ice particle number concentrations in the updraft core were a few particles L−1, which is similar to the primary ice nucleating particle (INP) number concentrations estimated from immersion freezing of high concentration dust particles in the convectively mixed boundary layer. The ice particle number concentrations were several tens of particles L−1 outside the updraft core in the upper levels. INP measurements and the observed cloud microphysical structure suggest that drizzles, frozen via the immersion freezing nucleation of dust particles, formed graupel embryos and ice particles, with concentrations of one to two orders of magnitude greater than those of the primary INPs, which may be generated via secondary ice production and/or ice particle accumulation from primary ice nucleation in clouds with relatively warm cloud top temperatures (approximately −12°C).

著者

Kenji Suzuki Rimpei Kamamoto Katsuhiro Nakagawa Michinobu Nonaka Taro Shinoda Tadayasu Ohigashi Yukiya Minami Mamoru Kubo Yuki Kaneko

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.15, pp.94-98, 2019 (Released:2019-05-14)

参考文献数

21

被引用文献数

5

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A field observation was carried out along the coast of the Japan Sea in the 2016-2017 and 2017-2018 winter seasons, using the Ground-based Particle Image and Mass Measurement System (G-PIMMS) to evaluate the Global Precipitation Measurement Mission (GPM) dual-frequency precipitation radar (DPR) precipitation type classification algorithm. The G-PIMMS was installed at Kanazawa University and Ishikawa Prefectural University, which are around 10 km apart from each other. The G-PIMMS observations showed that the major precipitation particle type (graupel or snowflake) was different in the precipitation types classified by the GPM DPR algorithm.

著者

WoonSeon Jung Masataka Murakami Taro Shinoda Masaya Kato

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.14, pp.197-202, 2018 (Released:2018-12-21)

参考文献数

19

被引用文献数

1

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The Cloud Resolving Storm Simulator (CReSS) model with default parameter settings largely underestimates the diurnal variation of land surface temperature (LST) and hence the formation of summertime diurnal convective clouds over the United Arab Emirates (UAE), which are the primary target of cloud seeding in the UAE. Based on sensitivity experiment results, we optimized a set of land surface parameters to minimize the underestimation of LST and improve the performance of weather simulations over deserts and mountains in the UAE. In the optimized experiment, the difference in LST between Aqua/MODIS observations and CReSS simulation results decreased from 13.0 to 2.3 K under daytime conditions, mainly due to decreased evapotranspiration efficiency and soil thermal diffusivity. Moreover, the difference decreased from 3.8 to 2.0 K under nighttime conditions, mainly due to decreased evapotranspiration efficiency and increased soil temperature at the deepest layer. A decrease in roughness length suppressed the increase in surface air temperature (SAT), contributing to the reproduction of a realistically large difference between LST and SAT during the daytime. The improvement in temperature matching demonstrates that the CReSS model, when used at a 1-km horizontal resolution, accurately simulates the formation of diurnal convective clouds and development of precipitation over deserts in the UAE and low mountains in northeastern UAE.

著者

Kenji Suzuki Rimpei Kamamoto Katsuhiro Nakagawa Michinobu Nonaka Taro Shinoda Tadayasu Ohigashi Yukiya Minami Mamoru Kubo Yuki Kaneko

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

pp.2019-018, (Released:2019-04-10)

被引用文献数

5

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A field observation was carried out along the coast of the Japan Sea in the 2016-2017 and 2017-2018 winter seasons, using the Ground-based Precipitation particle Image and Mass Measurement System (G-PIMMS) to evaluate the Global Precipitation Measurement Mission (GPM) dual-frequency precipitation radar (DPR) precipitation type classification algorithm. The G-PIMMS was installed at Kanazawa University and Ishikawa Prefectural University, which are around 10 km apart from each other. The G-PIMMS observations showed that the major precipitation particle type (graupel or snowflake) was different in the precipitation types classified by the GPM DPR algorithm.