Also Known as The Water Cycle The Hydrologic Cycle Also Known as The Water Cycle

The Hydrologic Cycle The water cycle renews Earth’s supply of fresh water.

Evaporation, Transpiration, & Sublimation Evaporation is the process in which water changes from liquid to gas. Approximately 80% of all water evaporates from oceans. The remaining water comes from fresh water sources and vegetation. Water evaporates more quickly when temperatures are warm. Transpiration is the evaporation of water into the atmosphere from vegetation including leaves and stems of plants. 10% of evaporating water is through transpiration. In sublimation solid water in the form of snow or ice changes to water vapor. In the world as a whole, the rates of evaporation and precipitation balance out each other.

Condensation & Transportation Condensation is when water changes from gas in the form of water vapor into liquid water. Condensation usually takes place when warm air rises then cools. At this time, the water vapor condenses into clouds. In the hydrologic cycle, transportation is the movement of water through the atmosphere. Most of the time, water moves through the atmosphere by the jet stream or by land and sea breezes from the area over the oceans to over land.

Precipitation Rain is moisture from the atmosphere that condenses and falls visibly in separate drops. Freezing rain falls as a liquid but freezes into glaze on contact with the ground. Hail is a type of precipitation that forms spherical or irregular pellets of ice larger than 5millimeters (0.2 inches) in diameter. Snow is frozen precipitation in the form of white or translucent hexagonal ice crystals that fall in soft, white flakes. Sleet is a form of precipitation consisting of generally transparent frozen or partially frozen raindrops Precipitation is the transporting of water from the atmosphere to the surface of the Earth through rain, freezing rain, hail, snow, or sleet. Droplets in a cloud grow bigger and bigger. Eventually, they become so heavy that they fall to the ground. Precipitation may vary at different locations on Earth from less than an inch to over one hundred inches annually.

What about the other parts?

Water Flow Water can return to oceans through surface runoff or groundwater. Surface runoff is when water moves across land to the oceans. This is normally in the form of rivers, lakes, and streams (areas of collection). Water always runs across a surface from higher elevation to lower. Groundwater is the water that has penetrated Earth’s surface and is in the soil layers. The process in which water seeps down into the ground is known as infiltration.

Infiltration The two forces that pull runoff into the soil are gravity and capillary action. Capillary action is the ability of a liquid to flow in narrow spaces without forces like gravity. Capillary movement creates an area above the water table that is saturated at various level depending on the size of the porous material in the space. Percolation is the slow movement of water through the pores in soil or permeable rock influenced by gravity.

Groundwater- water trickles down into the ground between particles of soil and cracks and spaces in layers of rock. Different types of rock have different- sized spaces (pores) between their particles. How easily water moves through a material depends on two things: The size of the pores Whether or not the pores are connected to each other Materials that easily allow water to pass through are called permeable. Materials that water cannot easily pass through are called impermeable.

Water Cycle Project Draw (create) a colorful diagram (slideshow or creative multi-media presentation) of the water cycle. Include everything that is necessary to explain visually how the water cycle works. You should show arrows to demonstrate the pathways that your droplet follows in your journey. Be sure to show the sun as it is the source that drives the water cycle. Label or identify the parts of the diagram (presentation) to accurately show condensation, evaporation, transpiration, precipitation, run-off, a collection area, and groundwater. Create a picture of yourself as a water droplet and show it in each part of your journey. Title your diagram , ___________’s Water Cycle Journey (insert your name) You will also have to provide a written explanation of our journey. Pretend for a moment in time that you are a water droplet that has just fallen from the sky. Create a homemade diagram (poster), a slideshow, or multi-media presentation that shows your journey (as a water droplet) through the water cycle. Your trip should take you through all stages of the water cycle (don’t forget to include transpiration). I should be able to easily follow the path that you took as a water droplet in your diagram (presentation). Your droplet should go through all stages in the cycle. All of the following must be included to earn the highest score.

Aquifer Project Visit Thirstin’s website for how to build an aquifer

The Water Table – Once water reaches an impermeable layer, it is trapped. It can’t soak any deeper. Instead the water begins to fill the spaces above the impermeable material. The area of permeable material becomes totally filled and is known as the saturated zone. The very top of the saturated zone is called the water table. This is the table that hydrologists study when determining if conditions are drought-like. Knowing the depth of the water table in an area, helps you to determine how deep you must dig to reach groundwater.

Aquifers Any underground layer of rock or sediment that holds water is called an aquifer. Aquifers can range in size from a small underground patch of permeable material to an area the size of several states. The huge Ogallala Aquifer lies beneath the plains of the Midwest, stretching from South Dakota to Texas.

Four Ways to Get Water out of the Ground Wells Artesian Well Spring Geyser Long ago, people dug wells by hand. They lined the sides of the well with brick or stone to keep the walls from collapsing. To bring up water, they lowered and raised a bucket. Water can be trapped between two layers of impermeable rock or sediment and puts the water under pressure Places where groundwater bubbles or flows out of the cracks in the rock A type of hot spring from which the water periodically burst into the air People can bring groundwater to Earth’s surface. Groundwater may also seep onto the Earth’s surface or feed a stream or pond, or form a wetland.

Well Drill a well so that it reaches below the water table, the very top of the saturation zone. Today , pumps bring up the groundwater. Pumping water out of an aquifer lowers the water level near the well. If too much water is pumped out too fast, the well may run dry. It will be necessary to either dig deeper to reach the lowered water table or to wait for rainfall to refill the aquifer. New water that enters an aquifer from the surface is called recharge.

Artesian Well Water can be trapped between two layers of impermeable rock or sediment and puts the water under pressure. This water is trapped under great pressure from the weight of the water above it. If the top layer of rock is punctured, the pressure sends the water spurting up through the hole. Water flows without pumping from such a well.

Spring Places where groundwater bubbles or flows out of the cracks in the rock Most springs contain water at normal temperature but some springs may be heated by hot rocks under the Earth’s surface.

Geysers A geyser forms when very hot water that has been circulating deep underground begins to rise through narrow passages in the rock. Heated gases and bubbles of steam are forced up theses passages by the pressure of the hot water boiling below. Just as pressure builds up in a partly blocked pipe, the pressure within the narrow openings in the rock increases. Finally, the gases, steam, and hot water erupt high into the air.