Year-to-year blooming phenology observation using time-lapse digital camera images

Shin Nagai, Shinpei Yoshitake, Tomoharu Inoue, Rikie Suzuki, Hiroyuki Muraoka, Kenlo Nishida Nasahara, Taku M. Saitoh

Research output: Contribution to journalArticle

10 Citations (Scopus)


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.

Original languageEnglish
Pages (from-to)163-170
Number of pages8
Journaljournal of agricultural meteorology
Issue number3
Publication statusPublished - 2014 Sep 10



  • Bio-meteorological observation
  • Blooming phenology
  • Cherry tree
  • Climate change
  • Time-lapse digital camera image

ASJC Scopus subject areas

  • Agronomy and Crop Science
  • Atmospheric Science

Cite this

Nagai, S., Yoshitake, S., Inoue, T., Suzuki, R., Muraoka, H., Nasahara, K. N., & Saitoh, T. M. (2014). Year-to-year blooming phenology observation using time-lapse digital camera images. journal of agricultural meteorology, 70(3), 163-170.