Land surface models (LSMs) are tools for helping society to predict how processes in multiple interconnecting domains (plant physiology, hydrology, soil biogeochemistry, snow science, land-atmosphere exchange, fire science, ecology, and crops) interact to mediate 1) the impact of climate change on the terrestrial surface of the earth. and 2) the feedbacks (biogeochemical and biogeophysical) they exert on the rest of the climate system.