Water Cycle. Are you really drinking the same water as the caveman?

Transcription

1 Water Cycle Are you really drinking the same water as the caveman?

2 Water Cycle Water is always on the move. Rain falling where you live may have been water in the ocean just days before. And the water you see in a river or stream may have been snow on a high mountaintop. The water cycle is also known as the hydrologic cycle. Fun Fact: Hydro is Latin for water

3 Where is water? Water can be in the atmosphere, on the land, in the ocean, and even underground. It is recycled over and over through the water cycle. In the cycle, water changes states between liquid, solid (ice), and gas (water vapor).

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5 Stage 1 : Evapora8on Evaporation is the change from liquid to vapor form. Evaporation turns the water that is on the surface of oceans, rivers, & lakes into water vapor using energy from the sun.

6 Stage 1 : Transpira8on When water evaporates from plants it is a process called transpiration. Plants lose water through their stems, leaves, and roots. A fully grown tree may lose several hundred gallons of water through its leaves on a hot, dry day.

7 Stage 2: Condensa8on Condensation is the process by which water vapor in the air is changed into liquid water. The water vapor rises in the atmosphere and cools, forming tiny water droplets by a process called condensation. Those water droplets make up clouds.

8 Stage 3: Precipita8on Those water droplets CONDENSE make up clouds. When those tiny water droplets combine with each other they grow larger and eventually become too heavy to stay in the air. Then they fall to the ground as rain, snow, and other types of precipitation. What are some other types of precipitation?

9 Stage 3: Precipita8on Precipitation is water released from clouds in the form of rain, freezing rain, sleet, snow, or hail. It is the primary way water is delivered from the atmosphere to the Earth.

10 Did you know How many gallons of water fall when 1 inch (2.5 cm) of rain falls on 1 acre of land? 27,154 gallons of water! Rain drops are not tear shaped. They start out in a ball shape, but as they fall they meet with air resistance, which starts to flatten out the drop until at about 2-3 mm in diameter the bottom is quite flat with an indention in the middle - much like a hamburger bun. When raindrops reach about 4-5 mm, things really fall apart. At this size, the indentation in the bottom greatly expands forming something like a parachute with two smaller droplets at the bottoms. The parachute doesn't last long, though, and the large drop breaks up into smaller drops.

11 Wow! That is amazing! Bonus Ques8on! The world's record for most average- annual rainfall belongs to. The world s recorded for least amount of rain goes to! It takes 6 gallons of water to grow the potatoes for your order of fries! For your hamburger it takes 1300 gallons of water to produce everything needed!

12 Stage 4: Runoff Runoff: The variety of ways by which water moves across the land. As it flows, the water may seep into the ground, evaporate into the air, become stored in lakes or reservoirs, or be extracted for agricultural or other human uses.

13 Stage 4: Infiltra8on Some of the precipitation seeps into the ground and becomes a part of the groundwater. That seepage is called infiltration.

14 Stage 5: Accumula8on The process in which water pools in large bodies (like oceans, seas and lakes) Most of the water on Earth is in the Ocean. Did you know? Water stays in certain places longer than others. A drop of water may spend over 3,000 years in the ocean before moving on to another part of the water cycle while a drop of water spends an average of just eight days in the atmosphere before falling back to Earth.

15 Ground Water

16 Ground Water Ground Water lies beneath the ground surface, filling pores in sediments and sedimentary rocks and fractures in other rock types Represents 0.6% of the hydrosphere (35x the water in all lakes and rivers combined) Resupplied by slow infiltra0on of precipita0on Generally cleaner than surface water Accessed by wells

17 Porosity and Permeability Porosity - the percentage of rock or sediment that consists of voids or openings Measurement of a rock s ability to hold water Loose sand has ~30-50% porosity Compacted sandstone may have only 10-20% porosity Permeability - the capacity of a rock to transmit fluid through pores and fractures Interconnectedness of pore spaces Most sandstones and conglomerates are porous and permeable Granites, schists, unfractured limestones are impermeable

18 The Water Table Subsurface zone in which all rock openings are filled with water is the saturated zone Top of the saturated zone is the water table Water level at surface of most lakes and rivers corresponds to local water table Above the water table is an unsaturated region Unsaturated zones made up of impermeable rock (e.g., shales or clays)

19 Ground Water Movement Movement of ground water through pores and fractures is rela0vely slow (cen8meters to meters/day) compared to flow of water in surface streams Flow velocity depends upon: Slope of the water table Permeability of the rock or sediment

20 Aquifers and Aquitards Aquifer - body of saturated rock or sediment through which water can move easily Sandstone Conglomerate Well- jointed limestone Sand and gravel Highly fractured volcanic rock

21 Confined vs. Unconfined Unconfined Aquifer Has a water table, and is only partly filled with water Rapidly recharged by precipita8on infiltra8ng down to the saturated zone Confined Aquifer Completely filled with water under pressure Separated from surface by impermeable confining laye Very slowly recharged

22 Springs Spring - a place where water flows naturally from rock or sediment onto the ground surface

23 Ground Water ContaminaBon Infiltra0ng water may bring contaminants down to the water table, including (but not limited to): Pharmaceu8cals Pes8cides/herbicides Fer8lizers Feed lots Mercury and gold mining Landfill pollutants Heavy metals Bacteria, viruses and parasites from sewage Industrial chemicals (PCBs, TCE) Acid mine drainage Radioac8ve waste Oil and gasoline

24 Groundwater Contamina8on WebQuest

25 Ground Water ContaminaBon Contaminated ground water can be extremely difficult and expensive to clean up

26 Caves, Sinkholes, and Karst Caves - naturally- formed underground chambers Acidic ground water dissolves limestone along joints and bedding planes Caves near the surface may collapse and produce sinkholes Rolling hills, disappearing streams, and sinkholes are common in areas with karst topography

27 Hot Water Underground Hot springs - springs in which the water is warmer than human body temperature Ground water heated by nearby magma bodies or circula8on to unusually deep (and warm) levels within the crust Hot water is less dense than cool water and thus rises back to the surface on its own Geysers - hot springs that periodically erupt hot water and steam

28 Geothermal Energy Geothermal energy is produced using natural steam or superheated water No CO 2 or acid rain are produced (clean energy source) Some toxic gases given off (e.g., sulfur compounds) Can be used directly to heat buildings Superheated water can be very corrosive to pipes and equipment

29 Streams and Groundwater Gaining streams - receive water from ground water Losing streams - lose water to ground water