著者

Masatoshi Kuribayashi Nam Jin Noh Taku M. Saitoh Ichiro Tamagawa Yasutaka Wakazuki Hiroyuki Muraoka

出版者

(公社)日本気象学会

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.9, pp.148-152, 2013 (Released:2013-10-11)

参考文献数

26

被引用文献数

3 8

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We estimated the snow water equivalent (SWE) of snowpack in central Japan from September 2006 to August 2008 by using a 3.3 km-mesh regional climate model with two land-surface models: Noah land-surface model (Noah LSM), and Noah land-surface model with multiparameterization options (Noah MP). The model validation for temporal variations of SWE at the Tohkamachi station and the comparison of modeled maximum SWE with estimated that from observed maximum snow depth at ten sites showed that Noah MP could simulate spatiotemporal variations of SWE better than Noah LSM which underestimated SWE. Simulated SWE in central Japan peaked in March, but the difference of SWE between the two land-surface models was greatest in April. SWE determined using Noah LSM (Noah MP) in analysis domain reached 18.1% (28.5%) of the total storage capacity of high dams in Japan in March 2007, whereas it reached 32.4% (44.1%) in March 2008. The difference of SWE between the two land-surface models was particularly high under warm conditions, that is, during the snowmelt season, and during a warmer than normal winter. Our results indicate that the choice of land-surface model for estimates of SWE is important under warm climatic conditions.

著者

Kazuo Kurihara Koji Ishihara Hidetaka Sasaki Yukio Fukuyama Hitomi Saitou Izuru Takayabu Kazuyo Murazaki Yasuo Sato Seiji Yukimoto Akira Noda

出版者

(公社)日本気象学会

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.1, pp.97-100, 2005 (Released:2005-09-14)

参考文献数

14

被引用文献数

36 48

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The Meteorological Research Institute (MRI) and the Japan Meteorological Agency (JMA) projected climate change over Japan due to global warming using a high-resolution Regional Climate Model of 20 km mesh size (RCM20) developed in MRI. Projection was made for 2081 to 2100 following a SRES-A2 scenario. Precipitation projected by RCM20 indicated that increased daily precipitation will be seen during the warm season from June to September. Except for this period, the precipitation amount will not change much or will slightly decrease around Japan. The increase during the warm season will be seen only in the western part of Japan. A possible cause of the increase is an El Niño-like SST pattern in the future. Due to the future increased summer SST in the eastern equatorial Pacific, anti-cyclonic circulation to the south of Japan will intensify and will induce a strong water vapor flux along the rim of the anti-cyclonic anomaly. The intensified flux will converge over the western part of Japan and may increase precipitation. Surface air temperature is projected to increase more than 2°C around Japan in January. In summer, the temperature increase will be lower by about 1°C than in winter.

著者

Hiroyuki Kusaka Haruka Kitahata

出版者

(公社)日本気象学会

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.5, pp.61-64, 2009 (Released:2009-04-29)

参考文献数

16

被引用文献数

1 3

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The synoptic-scale climatology of cold frontal precipitation systems during the passage over central Japan was investigated for 19 years (1988-2006). Cold frontal precipitation events are classified into the following three types: Widespread, Hokuriku, and Jump type. Widespread-type events, which bring precipitation throughout Japan, mainly occur in spring and autumn, and the cyclones tend to move northeastward from the central part of the Sea of Japan. The central pressure of the Widespread-type cyclones is the deepest and this type has the most moisture out of the three types. Hokuriku-type events, which bring precipitation exclusively over the Hokuriku area often appear in winter, and the cyclones move eastward from the northern part of the Sea of Japan. As a result, the isobars form in an east-west orientation over mainland Japan as the cold front arrives in the Hokuriku area. The Hokuriku-type cyclones tend to be relatively weak and there is less moisture during the events. For the Jump-type events, in which the precipitation distribution appears as precipitation bands jumping over the Kanto area, cyclones develop rapidly due to the deep trough at the 500 hPa level, changing the isobars from east-to-west to northeast-to-southwest during the events.

著者

H. Takagi T. Saeki T. Oda M. Saito V. Valsala D. Belikov R. Saito Y. Yoshida I. Morino O. Uchino R. J. Andres T. Yokota S. Maksyutov

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.7, pp.161-164, 2011 (Released:2011-10-29)

参考文献数

32

被引用文献数

43 54

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We assessed the utility of global CO2 distributions brought by the Greenhouse gases Observing SATellite (GOSAT) in the estimation of regional CO2 fluxes. We did so by estimating monthly fluxes and their uncertainty over a one-year period between June 2009 and May 2010 from 1) observational data collected in existing networks of surface CO2 measurement sites (GLOBALVIEW-CO2 2010; extrapolated to the year 2010) and 2) both the surface observations and column-averaged dry air mole fractions of CO2 (XCO2) retrieved from GOSAT soundings. Monthly means of the surface observations and GOSAT XCO2 retrievals gridded to 5° × 5° cells were used here. The estimation was performed for 64 subcontinental-scale regions. We compared these two sets of results in terms of change in uncertainty associated with the flux estimates. The rate of reduction in the flux uncertainty, which represents the degree to which the GOSAT XCO2 retrievals contribute to constraining the fluxes, was evaluated. We found that the GOSAT XCO2 retrievals could lower the flux uncertainty by as much as 48% (annual mean). Pronounced uncertainty reduction was found in the fluxes estimated for regions in Africa, South America, and Asia, where the sparsity of the surface monitoring sites is most evident.

著者

Yohei Takano Yoshihiro Tachibana Katsushi Iwamoto

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.4, pp.113-116, 2008 (Released:2008-10-08)

参考文献数

16

被引用文献数

20 24

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The characteristics of the anomalous winter climate around Japan in December 2005, including abnormally heavy snowfall, were analyzed from the viewpoint of interannual variation using reanalysis data for 50 years. The anomalous snowfall near the Sea of Japan in 2005 is attributed to an anomalous air-mass modification over the Sea of Japan, the large changes of thermodynamic characteristics due to the warmth of the Sea of Japan. Thermodynamic budget analyses showed that the air-mass modification in December 2005 over the Sea of Japan was the strongest in more than 40 years. Air-mass modification over the Sea of Japan was strongly related with a large-scale atmospheric north-south dipole pattern consisting of a northern high covering Siberia and a southern low covering a wide area of Japan in the 500 hPa height field in the positive phase (SJ pattern). In addition, the local SST variability during late autumn was significantly related to air-mass modification. However, the Arctic Oscillation was not significantly correlated with the air-mass modification over the Sea of Japan on an interannual timescale.

著者

Naoki Hirose Ken-ichi Fukudome

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.2, pp.61-63, 2006 (Released:2006-04-15)

参考文献数

8

被引用文献数

30 34

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Seasonal predictions of rain or snowfall are usually too uncertain at regional scales. We suggest utilizing subsurface ocean measurements to improve long-term weather forecasts. The example we give is that regional snowfall in Japan can be predicted by a simple regression from an acoustic Doppler current profiler attached to a regular ferryboat to observe the transport of the Tsushima Warm Current. The lag correlation is shown to exceed 0.75 attributed to the simple underling marine meteorology and regional oceanography. The relationship certainly improves seasonal precipitation estimates led by the winter monsoon absorbing the latent heat from the Japan Sea. We predict there will be less snowfall this winter of 2005/2006 than in 2004/2005 despite the heavy snowfall event in the last December.