Photosynthesis phenology, as defined by solar-induced chlorophyll fluorescence, is overestimated by vegetation indices in the extratropical Northern Hemisphere

Anping Chen, Colorado State University, Fort Collins, CO, United States, Fandong Meng, Institute of Tibetan Plateau Research, Peking, China, Jiafu Mao, Oak Ridge National Laboratory, Environmental Sciences Division and Climate Change Science Institute, Oak Ridge, United States, Daniel M Ricciuto, Oak Ridge National Laboratory, Environmental Sciences Division and Climate Change Science Institute, Oak Ridge, TN, United States and Alan Knapp, Colorado State University, Department of Biology and Graduate Degree Program in Ecology, Fort Collins, United States