Ideas in this flowchart

• Drought is a natural phenomenon involving shifts in the balance between precipitation and evapotranspiration.
• Drought involves an imbalance between precipitation and evapotranspiration.
• Evapotranspiration consists of evaporation and transpiration and is inherent to Earth’s water cycle.
• Several factors affect drought’s impact on humans and other life forms.
• The timing and effectiveness of precipitation affect drought’s impact.
• The characteristics of the built environment affect drought’s impact.
• Local demand for water affects drought’s impact.
• Communities can be affected differently by drought because of their local and societal conditions.
• Existing water systems, their structure, and their capacity influence community impacts.
• Economic development influences how communities experience drought.
• At-risk populations and local governance of water use influence drought impacts.
• Local social networks and other societal factors influence community vulnerability.
• Conditions signifying drought vary substantially by U.S. region and locality.
• Drought should be defined according to the context and location of the water shortage.