The snow meteorology and phenology classification (SnowMAP): global snow cover observations enhance snow's representation.

Snow is a vital water resource that regulates climate, supports ecosystems, and influences economies and transportation systems, making it essential to understand its physical properties and the seasonal timing of its presence (phenology). However, current snow classifications separate snow's meteorological controls from its phenology, limiting its decision-relevance. This study introduces SnowMAP, a global snow classification system that combines snow meteorological and phenology classes. By integrating meteorological factors such as snowfall, temperature, and wind with seasonal dynamics like snow presence and melt timing, SnowMAP provides a more complete view of global snow conditions. The resulting 18 snow classes reflect notable variations in snow depth, geography, land cover, and infrastructure. SnowMAP provides a unified framework for describing how a snowpack forms and evolves, enabling scientists, planners, and communities to better understand snow conditions and their impact on the natural and built environments.