Running Water & Groundwater Chapter 6 Mr. Litaker
The Water Cycle • Water constantly moves from the oceans to the atmosphere to the solid Earth and throughout the biosphere. • Why? * Because water can change b/w a solid, liquid, and a gas. Look at Figure 1 on page 158 Show slide presentation on Hydrologic Cycle.
Water Cycle • Water Cycle – This cycle of water movement is called the Hydrologic cycle.
WaterCycle • Transpiration – a process by which plants give off water vapor into the atmosphere.
Water Cycle • 86% of this water evaporates from the ocean. • The remaining 14% evaporates from lakes, streams, rivers and the soil or plants.
Water Cycle • Evapotranspiration– The processes of evaporation and transpiration.
Water Cycle • Condensation – When water vapor rises in the atmosphere, it expands and cools. As the vapor becomes cooler, some of it condenses or changes into tiny liquid water droplets, and forms clouds
Water Cycle • PrecipitationIs the process by which water falls from clouds to the earth’s surface as rain, snow, sleet, hail, and Virga.
Water • 75% of all precipitation falls on the earth’s oceans. • 25% falls on the land surface and becomes runoff or groundwater.
Infiltration or Runoff • Is the movement of surface water into rock or soil through cracks and pore spaces in Earth’s surface.
Water • Water Budget – The continuous cycle of evapotranspiration, condensation, and precipitation gives the earth its water budget.
Water • 2 Approaches to that can be used to ensure that enough fresh water is available today and in the future.
Water • 1 Conservation– enacting and strictly enforcing antipollution laws. • 2 Desalination – the process of removing salt from ocean water.
Earth’s Water Balance • This means that the total amount of water on the Earth remains balanced because The total amt. of annual precipitation of the Earth = the total amt. of water that evaporates. • Over land more - PRECIP. • Over Oceans More - EVAP.
Streamflow • ____________ influences the way water makes it to the oceans. The ability of a stream to Erode and Transport materials depends largely on its VELOCITY. What factors affect the Velocity of a stream??? Page 160
GR AD IE NT • Gradient – • Look at Figure 4 page 160 is the slope or steepness of a stream channel. The steeper the gradient the = The more ENERGY the stream has as it flows downhill.
Channel Characteristics • A Stream Channel – is the course water in a stream follows. • Where does the stream experience friction from? • What determines the amount of Friction?
Discharge • The Discharge of the stream is the VOLUME of WATER flowing past a certain point in a given amount of time. • Amt’s. change with rainfall & snowmelt.
Discharge How does Urbanization change the magnitude and frequency of Flooding??? Page 161
Discharge • Look at Table 1 on page 161
What is the Longest River in the U.S.? • The Missouri River is the longest. It begins in Montana and flows to St. Louis Missouri. • 4342 km or 2714 miles long • The Mississippi River (Headwaters) starts in Minnesota and flows to the Gulf of Mexico • 3757 km or 2348 miles long
Meanders • The BENDS in a river system are called Meanders. • AnIncised Meander is where the bend is cut off from the rest of the stream like the picture In figure 7 on pg. 163.
Tributaries A river system is made up of a main stream and all the feeder streams. • The land from which water runs off into these streams is called the Drainage Basin or watershed
River Systems – Stream Erosion • The path that a stream follow is called its channel • The process of lengthened and branching of a stream is called Headward Erosion.
stream piracy is a phenomenon occurring when a stream or river drainage system or watershed is diverted from its own bed, and flows instead down the bed of a neighbouring stream. This can happen for several reasons, including: 1.Tectonic earth movements, where the slope of the land changes, and the stream is tipped out of its former course. 2. Natural damming, such as by a landslide or ice sheet. 3. Headward erosion of one stream valley upwards into another • Stream Piracy or Headward erosion
River Systems – Channel Erosion • The materials carried by a stream are called stream load • Using a Graphic Organizer Use page 165 to Chart the 3 ways sediment is transported.
Most streams carry the largest part of their load _________________.
Stream Capacity • The capacity of a stream is directly related to its ________________. • What is a measure of the largest particles a stream can carry?
Water Beneath the surface Chapter 6.3
Movement of Water • When it rains, water can either soak into the ground or become runoff. • How much seeps into the ground depends on: • Steepness of slopes • Nature of surface materials • Intensity of rainfall • Type of vegetation
Zone of Saturation When it rains, most of the water seeps into the soil until it reaches the _________ ___ _________________. This area of groundwater within this zone is the ______________ _______.
Zone of Aeration • The area above the water table that is not saturated with water. • What little water there is in this area clings very tightly to rock and cannot be removed or pumped out.
Porosity • The percentage of the total volume of rock or sediment that consists of pore spaces. • Amt. of rainwater that can be stored underground depends on porosity.
Permeability When material can flow freely between rock layers by twisting and turning through interconnected openings the layer is said to bePermeable.
Clay is impermeable buthas a high porosity. Why? Because its pore spaces are so small WATER can’t move through them.
Aquitards An impermeable layer that will not allow water to pass. Aquifer Permeable rock layers or sediment that allow water to be transmitted freely.
Spring Forms whenever the water table intersects the ground surface.
HOT SPRINGS Areas where cooling igneous rock heat water below Earth’s surface to a temperature that is 6 to 9 degrees warmer than the air temperature where the spring occurs.
Geyser An intermittent hot spring or fountain in which a column of water shoots up with great force at various intervals.