Hydrology

Hydrology is the scientific study of the movement, distribution, and quality of water on Earth, encompassing the entire water cycle from atmospheric precipitation to surface and groundwater flow. As a key discipline within Earth and Atmospheric Sciences, it examines how water interacts with the land, shapes landscapes through erosion and deposition, and sustains ecosystems. The principles of hydrology are fundamental to solving critical societal challenges, including managing water resources, forecasting floods and droughts, and mitigating water pollution.

1. Introduction to Hydrology
   1. Definition and Scope of Hydrology
   2. Branches of Hydrology
      1. Surface Water Hydrology
      2. Groundwater Hydrology
      3. Hydrogeology
      4. Ecohydrology
      5. Urban Hydrology
      6. Agricultural Hydrology
      7. Forest Hydrology
   3. Interdisciplinary Connections
      1. Meteorology
      2. Geology
      3. Environmental Science
      4. Civil Engineering
      5. Geography
      6. Ecology
      7. Chemistry
   4. Historical Development of Hydrology
      1. Ancient Civilizations and Water Management
      2. Early Scientific Observations
      3. Development of Modern Hydrologic Science
      4. Key Historical Figures
      5. Evolution of Measurement Techniques
      6. Modern Computational Hydrology
   5. The Hydrologic Cycle
      1. Overview and Concept
      2. Components of the Hydrologic Cycle
         1. Precipitation
         2. Evaporation
         3. Transpiration
         4. Evapotranspiration
         5. Infiltration
         6. Percolation
         7. Surface Runoff
         8. Subsurface Flow
         9. Groundwater Flow
         10. Interception
         11. Depression Storage
      3. Global Water Balance
         1. Distribution of Water on Earth
         2. Oceanic Water Balance
         3. Terrestrial Water Balance
         4. Atmospheric Water Balance
      4. Residence Times of Water
         1. Atmospheric Residence Time
         2. Surface Water Residence Time
         3. Soil Water Residence Time
         4. Groundwater Residence Time
         5. Ice and Snow Residence Time
   6. Systems Approach in Hydrology
      1. Hydrologic Systems Concepts
         1. System Definition
         2. Open Systems
         3. Closed Systems
         4. Inputs and Outputs
         5. Storage Components
         6. System States
      2. Control Volumes
         1. Watershed as Control Volume
         2. River Reach as Control Volume
         3. Aquifer as Control Volume
      3. System Boundaries
         1. Physical Boundaries
         2. Temporal Boundaries
         3. Assumptions and Limitations
   7. Fundamental Hydrologic Equations
      1. Water Balance Equation
         1. General Form
         2. Components of Water Budget
         3. Application at Different Scales
         4. Temporal Considerations
      2. Energy Balance Equation
         1. Components of Energy Budget
         2. Net Radiation
         3. Sensible Heat Flux
         4. Latent Heat Flux
         5. Ground Heat Flux
         6. Role in Evaporation
         7. Role in Snowmelt