Post on 30-Dec-2015
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Do Now: Copy HW & Take a packet
Put WEATHER REVIEW HW on DESK
Earth Science Text Book HW:
Monday: Read p 300-305 Q’s 1-4
Tuesday: Read p 280 to 282 Q’s 1-5
Wednesday: Test Corrections
Thursday: Ground water practice problems
Friday: Lab Quiz Today, No HW
Extra Help: Thursday Morning & Lunch A days
Water Cycle
The process through which water is continuously circulating between the atmosphere and ground
EvaporationEvaporation
Transpiration
Animal Respiration
runoff
runoff
infiltrationinfiltration
infiltration
EVAPOTRANSPIRATION
The Water (Hydrologic) Cycle
-all the ways that water vapor enters the air
Condensation
Groundwater
Water that has infiltrated below the ground surface and is stored in pore spaces.
Water Table
-When precipitation hits the ground it will either infiltrate earth’s surface, run off, or
evaporate.-Infiltration can occur if the surface is permeable and unsaturated, and
if the land is gentle enough.-The rate of infiltration is
determined by the porosity and permeability of the soil.
Elements of the Water Budget
P All the PRECIPITATION that falls in one month
Elements of the Water Budget
PEP
All the PRECIPITATION that falls in one month
The ENERGY available to evaporate water Potential Evapotranspiration
Elements of the Water Budget
PEP
P- EP
All the PRECIPITATION that falls in one month
The ENERGY available to evaporate water
If P-EP > 0, then.... If P-EP < 0, then....There’s water left over There’s energy that can
still evaporate more waterWhen water is left over after evaporation, it can do either of 2 things..... Left over energy can
“look” for more water.....(where?)
Soak into the ground (“infiltrate”)
“Run off” in streams In the soil! (called “Storage”)
Draw this diagram in your notes
Label pore spaces and saturated zone and the zone of aeration, and the water table
Zones of Soil Water
Soil water movement
Porosity
Porosity is the amount of open space between soil particles
Porosity depends on how tightly packed particles are.
It also depends on particle shape and how well they are
sorted
PorosityPercent of open space in a material.
Factors that Effect Porosity
Shape Sorting Packing
Particle size does not effect porosity
Shape
Angular particles have lower porosityRounder particle have higher porosity
Particle Shape
Poro
sity
Sorting
Well sorted particles have higher porosity
Particle sorting
Poro
sity
PackingLoosely packed particles have higher porosity.
Packing
Poro
sity
If shape, sorting and packing are the same for samples with different sizes but
uniform shapes porosity will be the same.
35% 35%35%
Particle Size
Small
Large
Poro
sit
yH
igh
Low
Do Now: Focused Free Write
Consider two uniform samples of round sediments, Sample A are .5cm in diameter and Sample B are 2.0cm in diameter. Both samples are packed evenly, which sample has more porosity? Explain your reasoning.
Permeability
Permeability is the ability of water to pass through the soil.
The more open and interconnected the spaces are
between the particles the greater the permeability rate.
Permeability
Infiltration
Perm
eabili
ty
Permeability
Impermeable soil refers to soil that water CAN NOT Infiltrate
(seep through). If the ground is IMPERMEABLE the water will
become RUNOFF.Rapid = Permeable
No flow = impermeableDepends on interconnectedness of
pore spaces.
Runoff
Water that does not infiltrate the soil.Runoff occurs when the soil is saturated, the slope is steep or the ground is impermeable.
Runoff refers to the water that is not evaporated, and that does not soak into the ground. It is the water we find in streams.
Permeability
Permeability
Runoff
B. Factors Affecting Permeability Size: Large particles have higher permeability.
Clay is nearly impermeable
Hig
h
Particle SizeSmall Large
Perm
eabili
tyLo
w
B. Factors Affecting Permeability Soil Capacity: The amount of water that soil can hold, based on the porosity.
Saturated soil: pore spaces between soil particles are completely filled with water
Unsaturated soil: some pore space between soil particles are filled with air, so there is still room for water to infiltrate
The degree of saturation of the soil: the more saturated the soil already is , the less
infiltration.
B. Factors Affecting Permeability
3. Slope of the land- steeper the slope (gradient) the less infiltration.
Permeability
Slope of land
Perm
eabili
ty
Permeability and Vegetation
Vegetation Growing on the Soil
Vegetation: any plant life
Plant roots help create pathways for water to flow through into the ground.
Amt of VegPerm
eabili
ty
INFILTRATION
Infiltration refers to water soaking into the ground:
Infiltration rate
Slope
Infiltration rate
Permeability
Infiltration rate
Porosity
Infiltration rate
Soil Storage
Saturation
Do Now:
Take a lab from the Do Now Desk-HW on desk-Read the lab quietly to yourself
Capillary ActionCapillarity- attractive force between water and soil particles that prevents some of the water from moving downward.-The movement of water against the force of gravity The greater the surface area, the greater the capillarity, therefore it always depends on particle size. Smaller particles have more surface area and therefore more capillary action. Capillarity is why some water is retained in the intermediate belt in the diagram below called the capillary fringe.
CapillarityThe ability of water to rise in small
openings of soil or other materials, due to the forces of adhesion and cohesion.
The smaller the particles the greater the capillarity.
Particle SizeSmall Large
Capill
ar i
tyLo
wH
igh
Do Now:
Check board for name, please hand in missing progress reports
Focused free write:Define capillary action, which
particle size has the greatest potential for capillary action? Why?
% P = amount of water poured in (row 3)300 mL
RUNOFF & STREAM
DISCHARGE
RUNOFF & STREAM
DISCHARGE
Streams: Streams:natural channels which allow water to flow downhill
natural channels which allow water to flow downhill
DISCHARGE DISCHARGEVOLUME OF WATER FLOWING PAST A SPOT IN A GIVEN AMOUNT OF TIME
VOLUME OF WATER FLOWING PAST A SPOT IN A GIVEN AMOUNT OF TIME
A. Sources of water for
streams:
1.
2.
precipitationgroundwater
Factors Affecting Runoff and Stream Discharge
Stream discharge- volume of water flowing past a certain spot in a stream in a specific amount of time.
- most runoff gets into streams and as runoff increases,
discharge increases
Runoff Vs. Discharge
Runoff
Dis
charg
e
B. In moist climates, streams
are fed byGround water
HighWater Table
During dry spells
C. In dry climates, streams lose water to theground
LowWater Table
C. In dry climates, streams lose water to theground
LowWater Table
Factors that determine stream
discharge:A. Rainfall• time lag (between max. rainfall
and max. stream discharge)• takes time for runoff to reach the
stream
B.Vegetation:Increased vegetation blocks overland flow and slows stream response
C. Drainage basin or
Watershed•The land from which the water comes…….
That drains into the stream
•Large drainage basinmore discharge
•Small drainage basinless discharge
D. Type of Surface:
Rapid runoff if …..• ground is paved• impermeable (bedrock)• frozen
FLOODING:• Stream overflows its channel• precipitation rate exceeds
infiltration rate• hurricane- storm surges• impermeable ground (bedrock, frozen, paved, saturated already)
Factors Affecting Runoff and Stream DischargeRunoff occurs when 1. rate of precipitation exceeds the
of the earth’s surface.2. the pore space is3. the slope of the surface is too great to allow
to occur.
permeability rate
saturated
infiltration
Water Pollution
Two main types: point sourcepoint source – pollution from a single point of origin i.e. improper sewage systems, industrial waste.Nonpoint sourceNonpoint source – pollution from widely spread areas i.e. rainwater that carries pesticides and fertilizers, runoff from roads and parking lots.
Delta
1. Fan-shaped sediments deposits at the mouth of rivers and called deltas. The Nile, Amazon and Mississippi rivers have well-developed deltas
Alluvial Fan
1. Alluvial Fans form as the result of sediments being washed down a mountain.