- 著者
- Shin NAGAI Shinpei YOSHITAKE Tomoharu INOUE Rikie SUZUKI Hiroyuki MURAOKA Kenlo Nishida NASAHARA Taku M SAITOH
- 出版者
- 日本農業気象学会
- 雑誌
- 農業気象 (ISSN:00218588)
- 巻号頁・発行日
- vol.70, no.3, pp.163-170, 2014 (Released:2014-09-10)
- 参考文献数
- 26
- 被引用文献数
- 6 10
Long-term continuous phenological observation of cherry tree blooming is an important and challenging task in the evaluation of year-to-year weather and climate changes in spring in Japan. Here, (1) we performed daily field observations with a time-lapse digital camera in a deciduous broad-leaved forest in Japan from January 2004 to December 2013; and (2) we detected year-to-year variations in the blooming phenology of Prunus sargentii by visual inspection of the images and by image analysis. We found that (1) the red digital numbers (i.e., the digital intensity values of the red pixels; DNR) extracted from the time-lapse digital camera images tended to peak in full bloom; and (2) the green excess index (GEI) (based on the red, green, and blue digital numbers) tended to be lowest in full bloom. These results indicate that DNR and GEI are useful for detecting the timing of full bloom in P. sargentii.
- 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
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.