B.ed file

2. Name –
University Roll no.
Pedagogy II- Social Science
Topic – Water Cycle

3. The earth is
71% covered
by water...
Earth is the
only planet
known to have
water in all
three phases
(gas, liquid,
and solid)
It never
disappears, as
it is perfectly
recycled

4. Our Wonderful Water World
A solar-powered water world!

5. A water shortage?
 With a planet covered in water?
 With perfect solar powered recycling taking
place constantly?
 HOW can one claim that water is a resource
in crisis?

6. The Water Cycle... Perfect recycling
Ecclesiastes 1:7
All the rivers run into the sea; yet the sea is not full; unto the place from whence the
rivers come, thither they return again

7.  Ocean water 97.2%
 Polar Ice 2.15%
 97.2 + 2.15 = 99.35%
 .65% of global water supply is the amount
generally available for human use.

8. The problem with water…
 uneven distribution… some areas have too
much water, others much less than
necessary
 And when it is present, the water is often in
a condition that makes it unacceptable for
specific uses… e.g. salty or polluted or full
of sediment

10. The approximate location of the 100th Meridian… the traditional
dividing line between the humid east and the arid west

11. Water...

12. Water Use:
Withdrawal vs. consumption
irrigation consumes the
highest percent (81 percent)
commercial the lowest (1
percent)
The difference between the
volume of water withdrawn
and that consumed is the
return flow.

13. Irrigation
81% of water used for Irrigation is ‘consumed’...
Removed from the water system
(evapo-transpiration) and it is by far the most
consumptive use of water.
Technology has made irrigation much more
efficient....
Drip Irrigation has single emitters for each plant

20. How much water is consumed? How much is returned to the hydrologic cycle?

21. Issues: non-point source pollution
 The tragedy of the commons!
 Externalizing costs
 The 1977 “Clean Water Act” provided
federal guidelines and control over point
source pollution.
 Non-Point source pollution... Who is
responsible? How can it be controlled?
 Agricultural land use... The sacred institution
of ‘the family farm’

23. Ground Water…
 According to the USGS, in 2000 21% of
water used in the United States
 69.8 Billion gallons /day came from ground-
water sources
 68 percent, was used for irrigation
 19 percent was used for public water
supplies
 99% of ‘self supplied’ water sources were
ground water (a well)

24. http://ga.water.usgs.gov/edu/wugw.html

26. The Golan Heights...source region for the Jordan River
Even here, water has not been the source of conflict

27. THANK
YOU