Hydrological Cycle

• Water

  The liquid that allows life on Earth to exist. Water changes our world and practically every aspect of our existence as it cycles from the air to the land to the sea and back to the air again, repeating the cycle.
• Water cycle

  The continuous movement of water all around the Earth, driven by the Sun's energy.
• Significance of the Water Cycle

  • It allocates water to different places, regulates the weather, and cleans the water giving us fresh water that we may consume.
• Importance of Understanding the Water Cycle

  • Allows us to prepare and adapt to its process, observe its pattern which is useful for forecasts of meteorologists and to form strategies to manage our water resources.
• Processes of Water Cycle


  • Evaporation
  • Condensation
  • Precipitation
  • Sublimation
  • Deposition
  • Infiltration
  • Percolation
  • Runoff
  • Transpiration
  • Evapotranspiration
  • Canopy Interception
  • Advection
• Evaporation


  The process of liquid turning into a gas, this gas is called water vapor. This occurs because of heat that makes the water molecules move faster and faster, so fast that they eventually escape as gas.
• Evapotranspiration

  The process of water evaporating through the leaves of plants.
• Evaporation - When water evaporates from the oceans, the salt remains behind as it is denser and heavier than water vapor. This is why the water that evaporates from the oceans and forms clouds is not salty.
• Factors Affecting Evaporation

  • Temperature
  • Surface area
  • Humidity
  • Wind speed
• Condensation


  When the water vapor that has risen into the sky comes into touch with the colder air found up above, it dramatically cools. These vapors condense as a cloud, which is carried by air currents and winds as they move around the globe.
• Formation of clouds and fog

  • Condensation occurs when water vapor in the air cools down and transitions back into liquid form. This process requires specific conditions to take place.
• Types of Condensation

  • Clouds
  • Fog and mist
  • Frost
• Role of Temperature and Humidity in Condensation

  Temperature has the role of transporting and changing the water vapors. Humidity, which represents the amount of water vapor in the air, also influences condensation.
• Precipitation


  Any liquid or frozen water that forms in the atmosphere and falls back to the earth. It takes several forms, including rain, sleet, and snow.
• Rainfall explanation

  When the temperature is above freezing point (0 degrees Celsius), water vapors in the air will condense and form water droplets. However, this condensation process requires the presence of dust particles or other impurities as nuclei for the droplets to form around.
• Snowfall explanation

  In very cold temperatures or under extremely low air pressure, the water droplets freeze and descend as snowflakes or hailstones.
• Types of Precipitation

  • Rain
  • Snow
  • Sleet
  • Hail
• Factors Influencing Precipitation Patterns

  • Prevailing winds, the presence of mountains, and seasons.
• Sublimation


  The process of a solid (especially snow or ice) turning into a gas (water vapor) without becoming liquid. It usually occurs as a result of dry winds and low humidity.
• Deposition


  The exact opposite of sublimation where gas turns into solid directly.
• Runoff


  The water, being on the ground, is being pulled to its resting point where some of it is compiled into a body of water until it reaches the ocean.
• Pathways of Runoff


  • Streams - When it rains, the water that does not soak into the ground or being absorbed by plants begins to flow across the land surface. This extra water collects and forms little channels known as rills, which eventually connect to form bigger channels known as streams.
• Infiltration


  When rainwater seeps into the ground, it undergoes infiltration, with the absorption level depending on the type of material it permeates.
• Percolation


  The process of water moving downward through soil or porous materials. It involves water seeping through the spaces between soil particles.
• Importance of Infiltration and Percolation in Groundwater Recharge

  • Vital processes for groundwater recharge, providing a constant supply of water for a variety of uses.
• Transpiration


  The process by which water evaporates into the atmosphere through plants. Plants absorb water and nutrients from the underground through their roots, and some of this water is then released through specialized structures called stomata, located on the underside of the leaves.
• Influence of Environmental Factors on Transpiration Rates

  • Temperature
  • Humidity
  • Light Intensity
  • Soil Moisture
• Impact of Human Activities on the Water Cycle

  • Humans have a great impact on the water cycle, but sadly mostly not great impacts activities like damming rivers for hydroelectricity, using water for farming, deforestation, and the burning of fossil fuels disrupt the water cycle.
• Effects of Climate Change on the Water Cycle

  • Increased Evaporation
  • Changes in Precipitation Patterns
  • Melting Glaciers and Ice Caps
  • Increased Water Stress
• Water is essential for all forms of life and plays a vital role in sustaining life on Earth.
• The water cycle, or hydrologic cycle, is the continuous movement of water on Earth through processes like evaporation, condensation, precipitation, infiltration, percolation, transpiration, and runoff.
• Importance of Ongoing Research and Understanding of the Water Cycle

  • Ongoing research on the water cycle helps in managing water resources effectively, improving climate prediction and weather forecasting, assessing the impact of changing precipitation patterns and temperature on ecosystems, identifying sources of pollution and developing strategies for water quality management, and informing strategies for optimizing water use in agriculture, industry, and households.
• Encouragement For Individual and Collective Actions to Protect and Conserve Water Resources

  • Raise awareness and provide education about the importance of water conservation and the consequences of water scarcity
  • Implement policies and regulations that promote water-saving practices and technologies
  • Offer economic incentives such as pricing structures and subsidies to motivate water conservation
  • Engage communities through programs and events that encourage active participation in water conservation efforts
  • Embrace technological advancements that enable efficient water use and conservation
• Factors Affecting Evaporation

  Temperature - the higher the temperature the higher the evaporation is.
• Factors Affecting Evaporation


  Surface area - the flatter the surface area (increases), the higher the evaporation is.
• Factors Affecting Evaporation

  Humidity - The higher the humidity the higher the evaporation rate.
• Factors Affecting Evaporation

  Wind speed - This is when the wind speed increases, the rate of evaporation also increases.
• Rain


  Rain is the most frequently observed type of precipitation. Raindrops that exceed 0.02 inches or 0.5 mm in diameter are commonly recognized as raindrops.
• Snow


  Snow is a form of precipitation that descends from the atmosphere as tiny ice crystals. These snow crystals typically exhibit a branched and star-like structure with six distinct points. They are created when water vapor in the clouds freezes and subsequently falls to the ground.
• Sleet


  Sleet is a form of precipitation that consists of frozen raindrops or snowflakes that have undergone a process of refreezing after reaching the ground.