Transcript Water - S3 amazonaws com

Water Movement
The World’s Water
• 97% Salt Water
• 2.5 % Frozen Fresh
Water
• .5% Usable Fresh
Water
Water Cycle
• Hydrosphere- water
of Earth’s surface
• Water Cyclemovement of water in
the hydrosphere,
driven by sunlight
Water Cycle
Water Cycle
Recharge
• Rains more than
plants use
• Extra water stored in
soil
• In rain forests extra
water produces water
vapor which creates
rain
Surplus
1. Rain Continues
2. Soil becomes full
3. Extra water runs off
4. Water Table raises at
times flood occur
Usage
• Plants use more water
than it rains
• Plants Draw from soil
supply
Deficit
• Need for moisture
continues
• Soil Storage runs out
Water Budget Graphs
• Water budgets
describe how much
water is received and
used in a region
• Graphs show the
moisture supply
versus the moisture
need for a region
Can Rocks Hold Water?
• Porosity- percentage
of a volume that is
pore space
• Shape- more round
increases porosity
• Sorting- poorly sorted
reduce porosity
• Cement filling
reduces porosity
Permeability
• Rate that liquids go
through pore spaces
• Increases with
porosity (NOT
ALWAYS TRUE)
– Holes must connect
• IMPERMEABLEliquid can’t get
through
Capillary Water
• Water that sticks to
grains
• Only
evapotranspiration
can remove it
Water Table
Water Table
• Depth depends on rainfall, season, soil
thickness, climate
• Water Table is at the surface at swamps,
lakes, rivers etc.
• Hundreds of meters below surface in
deserts
• Few meters below surface in forests, farms
Wells
• Ordinary Wells- holes
dug down to the water
table to bring
groundwater up
• Wells must be dug
below the lowest level
the water table could
fall to during dry
seasons
Aquifers
Aquiferspermeable
materials
that carry
groundwater
Artesian Formations
Artesian
Formationaquifer under
nonporous
layers holds
groundwater
Artesian Wellsrelease water
from Artesian
formations
Groundwater Pollution
• Fertilizers, Toxic
chemicals and even
salt can get into
groundwater as it
moves through the
soil
• Restricting use of
these pollutants can
help clean up water
Conserving Groundwater
• Excess use of
groundwater can
lower the water table
• Artificial methods of
groundwater recharge
can help refill the
water table
Water Temperatures
• Water below the
surface (up to 20m)
remains the average
temperature for that
region
• If average temp is
below freezing
water is permanently
frozen PERMAFROST
Water Temps
• Below 20m temps rise 1°C for every 40m
• Deep wells or springs may have warm
water
Paint Pots
• Volcanic activity can
also heat water to
boiling temps
• Paint Pot- hot water
comes up through
thick clays
Geysers
• Boiling hot springs
that gush hot water
and steam
periodically
• Blockages or
constrictions in the
waters path to the
surface put it under
pressure
Fumaroles
• Hot gas and steam
escape from cracks in
the ground
Minerals in Groundwater
• As water goes through the soil it dissolves
minerals
• Type of soil, temperature and length of
passage determines mineral content
• Hard water contains many ions, especially
calcium
• Artesian water is harder than groundwater
• Groundwater is harder than river water
Mineral Springs
• Contain to many
minerals to drink
• Caused by
– easy dissolved rock
– acids in water
– Water is hot, minerals
dissolve easier
Caverns
• CO2 in the air
dissolves into rain
• Carbonic Acid is
created
• Limestone
underground is
dissolved by carbonic
acid in water
Sinkholes
• If the cave roof
dissolves or
falls in a
sinkhole forms
Karst
• Regions with lots of
sinkholes, sink ponds,
caves and lost rivers.
• Lost rivers form when
streams flow underground
and resurface kilometers
away
• Major areas MI, S.
Indiana, Kentucky, Tenn,
Florida
Dripstones
• Calcite deposit from
dripping water
• Stalactites- hang from
ceiling
• Stalagmites- come up
from the ground
• Pillars- form when the
two meet
Travertine
• Calcite deposit around
a mineral spring
Geyserite
• Silica deposit formed
from the hot igneous
rocks the water passed
through
Petrified Wood
• Minerals dissolved in
water replace the
decaying wood of
buried trees