Modeling grassland spring onset across the Western United States using climate variables and MODIS-derived phenology metrics

• DOI: 10.1016/j.rse.2015.02.003
• Publication Date: 2015-02-20T11:41:06Z
• Authors: Qinchuan Xin; Mark Broich; Peng Zhu; Peng Gong
• Keywords: 13. Climate action; 15. Life on land; 01 natural sciences; 0105 earth and related environmental sciences

Abstract Vegetation phenology strongly controls photosynthetic activity and ecosystem function and is essential for monitoring the response of vegetation to climate change and variability. Terrestrial ecosystem models require robust phenology models to understand and simulate the relationship between ecosystems and a changing climate. While current phenology models are able to capture inter-annual variation in the timing of vegetation spring onset, their spatiotemporal performances are not well understood. Using green-up dates derived from MODIS, we test 9 phenological models that predict the timing of grassland spring onset via commonly available climatological variables. Model evaluation using satellite observations suggests that Modified Growing-Degree Day (MGDD) models and Accumulated Growing Season Index (AGSI) models achieve reasonable accuracy (RMSE