1. Do Now: What is the difference between weather and climate?
On Earth why do you think we care about water so much?

2. Chapter 8 Water :pages

3. The Water Cycle why is ground water so important? video
Water cycle (hydrologic cycle) – model used to illustrate movement / phase changes of water
Driven by solar energy (insolation)
Most water on Earth in Oceans
Less than 1% of water on Earth is drinkable
97.2% in Salt Water (Oceans)
2.2% Icecaps and Glaciers

4. Rain and then what? Things that happen to precipitation:
Water retention – stored on land as ice or snow, held on leaves
Infiltration (seep) – water sinks into the ground
Runoff – flow over surface ofland
Evapotranspiration – evaporation and transpiration (into atmosphere)

6. Factors Affecting Infiltration
Infiltration: When water seeps into the ground and becomes subsurface water or groundwater
Infiltration occurs in the regolith - all loose material at the Earth’s surface
1. Slope steeper slope (gradient) = less infiltration
INFILTRATION
GRADIENT

7. 2. Porosity- The amount of open space in between sediments
The greater the porosity the greater the infiltration
INFILTRATION
POROSITY

8. Porosity is determined by:
a. Shape - Well rounded particles have greater porosity than angular.
ROUND
ANGULAR
POROSITY
ROUNDNESS

9. b. PACKING- The more closely packed the particles the lower the porosity.
UNPACKED
PACKED

10. - If all particles are the same size they are sorted.
c. SORTING-
- If all particles are the same size they are sorted.
- If the particles are different sizes/mixed they are
unsorted (poorly sorted)
- The more sorted the higher the porosity
POROSITY
SORTING

11. Particle Size alone does NOT affect porosity
Particle Size alone does NOT affect porosity!!!!! (Shaping, Packing, Sorting does)

12. Back to factors affecting infiltration…

13. The more saturated the regolith, the less the infiltration
3. Degree of saturation- how much water seeps into those open pores of the sediment determines how much it can absorb
The more saturated the regolith, the less the infiltration
INFILTRATION
SATURATION

14. The more permeable the regolith, the greater the infiltration
4. Permeability- The ability of a material to allow fluids to pass through it
Impermeable = means water cannot pass through (Ex: clay layers in ground)
The more permeable the regolith, the greater the infiltration
INFILTRATION
PERMEABILITY

15. Porosity is not the same as permeability!

16. Capillarity Capillarity increases with a decrease in particle size.
Capillarity- Water sticks to the materials that it is
passing through.
Capillarity increases with a
decrease in particle size.
*Fine sand has greater capillarity than coarse sand
CAPILLARITY
PARTICLE
SIZE

17. 5. Capillarity- Water sticks to the materials that it is passing through
The greater the capillarity, the less the infiltration
INFILTRATION
CAPILLARITY

18. Follow up Work: Porosity/Permeability Relationships Packet
Time for an activity!
Follow up Work: Porosity/Permeability Relationships Packet

19. Plants slow precipitation down, giving the water more
6. Vegetation-
Plants slow precipitation down, giving the water more
time to infiltrate into the ground
No vegetation = high runoff
INFILTRATION
VEGETATION

20. Roads and buildings are impermeable, reducing infiltration
7. Construction –
Roads and buildings are impermeable, reducing
infiltration
INFILTRATION
CONSTRUCTION

21. Factors Affecting Runoff and Stream Discharge
1. Rate of precipitation greater than infiltration or permeability

22. Runoff and Stream Factors (cont)
The pore space of material / rock saturated with water
The slope of surface too great
Water has not evaporated or sublimated into a gas
Stream Discharge = volume of water flowing past a point
Greater runoff = greater stream discharge

23. California Mudslides
Identify all factors in the following video to explain why N. California experienced such torrential mudslides

24. Las Vegas Flash Flood
Identify 3 reasons why Las Vegas was prone to flash flooding during this time

25. Ground Water Zone of Aeration- The pores between particles are
mostly filled with air
Zone of Saturation- The pores between particles are
completely filled with water (Ground Water)
Water Table - Where the zone of aeration and zone of
saturation meet

26. More Realistic View

28. FINE SAND Moderate drainage
PERMEABILITY
GRAVEL  Rapid drainage
 FINE SAND Moderate drainage
 CLAY Slow drainage

29. Porosity and Permeability of Soils Lab

31. Other Activities
Complete Porosity/Permeability/Capillarity worksheet