 The Green Red Vegetation Index, GRVI, was evaluated as a phenological indicator based on multi-year stand level observations in Japan, revealing its ability to detect seasonal changes in vegetation and ground surface with high temporal resolution, and showing advantages such as a single threshold for early leaf green up and autumn coloring, and distinct responses to disturbance and ecosystem types. This article was authored by Takishimotooka, Kenlo Nishida-Nasahara, Satoshi Sachida, and others.