Land and Water JoAnn Lawall Grade 4 Goodnoe Elementary School 3/15/11  Overview video Overview video Overview video  Model – how scientists represent complex events to help understand them better  Fresh water – about 2.8% of the world’s water Fresh water – about 2.8% of the world’s water Fresh water – about 2.8% of the world’s water

The Water CycleThe Water Cycle – it’s a continuous process (Lesson 1 & 2) The Water Cycle  Precipitation Precipitation  Evaporation Evaporation  Condensation Condensation  Water cycle.html Water cycle.html Water cycle.html

The Water Cycle  Precipitation Clouds gather excess water Clouds gather excess water Water falls back to earth Water falls back to earth HailHail RainRain SnowSnow SleetSleet  Drought – long periods without precipitation

The Water Cycle  Condensation Water vapor rises Water vapor rises Cold air forms in the atmosphere Cold air forms in the atmosphere Water vapor clings to particles of dust Water vapor clings to particles of dust Cold air turns droplets to particles Cold air turns droplets to particles Droplets combine to form clouds Droplets combine to form clouds Droplets combine to form clouds Droplets combine to form clouds

The Water Cycle  Evaporation The sun heats the earth The sun heats the earth Water changes to gas (water vapor) Water changes to gas (water vapor) Minerals are left behind Minerals are left behind

Other related concepts…  Transpiration – plants “sweat” or lose water into the atmosphere Transpiration  Hydrologist – scientists who study water on the earth and in the atmosphere  Geologist – scientists who study landforms

Watershed

Modeling Rain  Precipitation – it goes several places surface waters (streams, lakes, oceans, etc.) surface waters (streams, lakes, oceans, etc.) the ground the ground evaporates into water vapor evaporates into water vapor Runoff of impervious surfaces and saturated land Runoff of impervious surfaces and saturated land Runoff of impervious surfaces and saturated land Runoff of impervious surfaces and saturated land

Examining Earth Materials (Lesson 5)  Two types of matter Inorganic – weathered rock fragments; never alive Inorganic – weathered rock fragments; never alive Organic – living and decaying plant and animal materials Organic – living and decaying plant and animal materials

Four Soil Components  Gravel Inorganic Inorganic Heaviest, biggest particles Heaviest, biggest particles Colored - tan, white, brown, gray Colored - tan, white, brown, gray Sinks in water Sinks in water

Four soil components continued…..  Sand Inorganic Inorganic Lighter than gravel Lighter than gravel Grainy texture Grainy texture Colored – white, gray, tan Colored – white, gray, tan Clumps in water Clumps in water Floats Floats

Four soil components continued…  Clay Inorganic Inorganic Lightest soil Lightest soil Powdery Powdery Orange-brown Orange-brown Suspends in water Suspends in water

Four soil components continued…….  Humus (top soil) Organic Organic Loose texture Loose texture Large and small pieces Large and small pieces Holds a lot of water Holds a lot of water Clumps Clumps Floats, then sinks Floats, then sinks

Where Does Water Go? (Lesson 6)  Water seeps into ground between soil particles or under the force of gravity  Water seeps into ground between soil particles or pore space under the force of gravity  Pore space – space between soil particles  Gravity – force that pulls matter to earth

Where Does Water Go?  Impervious – layers of rock, water flows off or around it  Runoff – water that flows over land Runoff  Compaction – the degree to which soil packs together

Water Table  Underground boundary between zone of saturation (land filled with water) and the zone of aeration (land filled with air and soil.) Underground

Investigating Streams  Origin of streams streams Flowing water or precipitation Flowing water or precipitation Melting snow and ice Melting snow and ice Melting snow and ice Melting snow and ice Underground springs Underground springs Underground springs Underground springs Water that flows out of cavities or caves (aquifers)Water that flows out of cavities or caves (aquifers) Groundwater dischargeGroundwater dischargeGroundwater dischargeGroundwater discharge

Investigating Streams continued….  Different forms of streams….. Rivulets – tiny channels that form gullies Rivulets – tiny channels that form gullies Gullies – deeper channels Gullies – deeper channels Tributaries – small stream branches Tributaries – small stream branches Rivers – joined streams and tributaries Rivers – joined streams and tributaries

Investigating Streams continued….  Parts of a stream channel (trunk) Head – top of stream Head – top of stream Delta – triangular –shaped landform created by deposited sediment Delta – triangular –shaped landform created by deposited sediment Mouth – where the bottom meets larger body of water Mouth – where the bottom meets larger body of water Floodplain – land left behind after flood waters drain (often covered after heavy rain flows) Floodplain – land left behind after flood waters drain (often covered after heavy rain flows) Tributary – branches of stream Tributary – branches of stream

Erosion & Deposition (Lesson 7 & 8)  Aerial drawing – “bird’s eye view” ; view of stream model from above  Velocity – the speed of water flow

Erosion & Deposition continued….  Weathering - the process by which rocks break down into various earth materials including soil  Erosion – the wearing away of land Wind Wind Waves Waves Flowing water or precipitation Flowing water or precipitation Flowing water or precipitation Flowing water or precipitation Glaciers Glaciers

Erosion & Deposition continued….  Deposition – the soil which is moved by water  Sediment – another way to describe deposition  Suspension – when fine particles float in water and do not dissolve  Load – large amount of sediment Causes an overflow of water Causes an overflow of water

Glaciers  Moving rivers of ice  Usually only moves a few inches a day

Modeling Tributaries (Lesson 9)  Stream trunk and its tributaries act as a system for draining land  Watershed – all of surrounding area drained by stream channel and tributaries

Hills and Rocks: How Nature Changes the Direction and Flow of Water? (Lesson 11)  What Is An Oxbow Lake? An oxbow is a crescent-shaped lake lying alongside a winding river. The oxbow lake is created over time as erosion and deposits of soil change the river's course. You can see how an oxbow lake takes shape below:

Oxbow Lake

Dams: How Humans Change the Direction and Flow of Water (Lesson 12)  Flood-control dams – a barrier that controls the direction and flow of water Main purpose is to hold excess water from a storm Main purpose is to hold excess water from a storm  Reservoir is an artificial lake created for excessive runoff  Hydroelectric power – stored water generates electricity

“Dams” continued  Flood – caused by a severe storm which can cause a stream to overflow its banks  Flash flood - sudden increase in runoff due to heavy flood of water  Levee – high ridges along banks that prevents or minimize flooding

“Dams” continued  Ecosystem – environment in which plants and animals live and interact  Irrigation – brings water to farmland through drainage channels that provides water for growing crops