This document discusses various topics related to environmental science and engineering including renewable energy resources, floods and drought, agriculture, and water resources. It provides details on different types of renewable energy such as solar, wind, hydro, and geothermal power. It also describes the causes and impacts of floods and droughts. The document outlines sustainable agriculture practices like crop rotation, contour farming, and intercropping to prevent overgrazing. It provides an overview of the hydrologic cycle and different freshwater reservoirs including rivers, lakes, and groundwater aquifers.

1. ENVIRONMENTAL SCIENCE AND
ENGINEERING

2. TOPICS
• Renewable energy resources
• Floods and drought
• Agriculture and over grazing
• Water resources

3. Renewable energy resources
• Solar energy
• Wind energy
• Water energy
• Geo thermal energy

4. Solar energy

5. At focal point = heat liquid – steam to turn
turbine

7. Solar electricity generation

8. Solar water heating solar air heating

9. Solar house problems
• The Los Angeles air = smog
• Retrofitting- very expensive
• Hard for big hotels, Wal-Mart's, etc.

10. Wind energy
Banning Pass

11. Wind Power Generation

12. Netherlands = coastal development

13. England = off shore

14. Wind energy problems
• Location – near population center
• Bird migration –
• Visual
• Must be coupled with other sources of
electricity (intermittent supply)

15. Hydropower

16. Problems with hydroelectric
• Location = unused rivers are in extreme north
or low population areas
• Competition with recreational uses (U.S.) and
environmental concerns
• Hard to build dams in populated river valleys
• Siltation of dams – limited life.

17. Tidal power
1.In areas of large tides
2.Anywhere – build offshore dam

18. Tidal power anywhere
1.No dam – but a turbine.
Problems:
1. Corrosion
2. Navigation
3.Amount of energy
available is low
4.Best tides are near
poles – away from
people.

19. Geo thermal energy
Heat near surface of
the earth = geysers,
volcanoes, etc,,.

20. Use heat to make steam to turn turbine for electrical
generation
Note: deep hot waters are corrosive to best to inject clean
water in a closed system and bring it back to the surface as
steam.
Geothermal Energy

21. Floods and Droughts

22. Causes OF Floods
• Floods are an excess of
water that covers land
that is normally dry.
• This can be due dam or
level failures, more rain
than the landscape can
dispose of, torrential
rains caused by storms,
rapid snow melts, or a
blocked river.

23. Causes OF Droughts
• it is caused by a lack of
precipitation in an area
resulting from weak or less
frequent storms and other
weather systems than
normal.
• Most major droughts last
for months or years.
• What is considered a
drought in a rainy location
may be enough
precipitation for another
region.

24. When Do They Occur?
• Floods can occur any
time of the year.
• Floods occur primarily
in the spring season due
to ice and snow melting
and frequent storms.
• In some countries,
there are monsoon
seasons, a time of great
rain, when floods often
occur, then a dry
season, when drought
conditions occur.
• Droughts can occur any
time of the year.
• In North America,
droughts occur most
often between March
and September, when it
is often dry and hot.

25. Major River Floods
The areas in red are where river floods
have occurred this year.

26. Other Facts
• Floods account for 40% of all deaths caused by
natural disasters.
• In an average year, floods account for about 200
deaths and $2 billion of damage in the U.S. alone.
• In 1937 floods removed 300 million tons of
topsoil in the Ohio Valley.
• The world’s longest drought occurred in Arica,
Chile, from October 1903 to January 1918. No
rain fell for over 14 years.

27. AGRICULTURE
Crop rotation
• Alternating the crop planted (e.g., between corn and
soybeans) can restore nutrients to soil and fight pests
and disease.

28. Contour farming
• Planting along contour lines of slopes helps reduce
erosion on hillsides.

29. Intercropping
• Mixing crops such as in strip cropping can provide
nutrients and reduce erosion.

30. Alley cropping

31. Terracing
• Cutting stair steps or terraces is the only way to farm
extremely steep hillsides without causing massive erosion.
It is labor-intensive to create, but has been a mainstay for
centuries in the Himalayas and the Andes.

32. Shelterbelts
• Rows of fast-growing trees around crop plantings
provide windbreaks, reducing erosion by wind.

33. Overgrazing
• When livestock eat too much plant cover on
rangelands, impeding plant regret
• The contrast between ungrazed and overgrazed
land on either side of a fence line can be striking.

34. Overgrazing
• Overgrazing can set in motion a series of positive
feedback loops.

35. Effects of overgrazing
Land degradation Soil erosion

36. Water resources
• Hydrologic Cycle
• Water Reservoirs

37. Hydrological cycle

38. Hydrological cycle

39. Freshwater Reservoirs
• Rivers and Streams
• Lakes
• Groundwater

40. Freshwater Reservoirs
River and streams lakes

41. Groundwater
• Much greater in volume than either lakes or
streams
• renewable in our lifetime

42. AQUIFER
• Geologic formation that possesses porosity and
permeability

43. Confined and unconfined aquifers

45. THANKYOU
• BY
– K.V. VARUN
KARTHIKEYAN