Concepts

Standardized measure of water deficit calculated using the Standardized Precipitation Evapotranspiration Index (SPEI) over 12-month periods

Soil electrical conductivity measured via electrical resistivity tomography to estimate soil moisture and subsurface properties

Geophysical method using electromagnetic waves to measure subsurface properties including snow density through travel-time analysis

The slope of peak NDVI as a linear function of the June Palmer Drought Severity Index, representing plant productivity responses to early growing season drought conditions

The number and extent of fractures in bedrock that control fluid flow and transport properties