Spring leaf and bloom index dates (1880-2013) and migratory bird flyways

This page contains NetCDF files of the Spring Leaf and Bloom Indices spanning 1880-2013. These files were created and are maintained by the USA National Phenology Network (www.usanpn.org). The Extended Spring Indices are mathematical models that predict the "start of spring" (timing of leaf out or bloom for species active in early spring) at a particular location (Schwartz 1997, Schwartz et al. 2006, Schwartz et al. 2013). These models were constructed using historical observations of the timing of first leaf and first bloom in a cloned lilac cultivar (S. x chinensis 'Red Rothomagensis') and two cloned honeysuckle cultivars (Lonicera tatarica 'Arnold Red' and L. korolkowii 'Zabelii'). Primary inputs to the model are temperature and [...]