Water is a key component of the overall Earth system, cycling through each component, moving within the atmosphere, the ocean, the cryosphere — including snow cover and snowpack — surface water of rivers and lakes, and subsurface water. Water availability is critical for ecosystem health as well as human survival and activities including agricultural production and natural resources industries.

One important measure of water in the system is soil moisture. Adequate soil moisture is vital for crop growth and yield, while extremely high or low amounts can negatively impact crop growth. Timely seasonal soil moisture information enhances food security and provides the ability to detect drought and other water-related stressors, such as root rot, on crop production. 

NASA offers soil moisture datasets that indicate the amount of water at a specific location in the soil profile, based either on depth or infiltration time. The data is provided by platforms such as the Soil Moisture Active Passive (SMAP) satellite and computer models from the Land Data Assimilation System (LDAS).