1. Severe Weather
Thunderstorms
Lighting occurs when current flows between the regions in the clouds w/ opposite electrical charges
Thunder results from the rapid heating of air around a flash of lighting (air expands rapidly forming sound waves)

2. Severe Weather
2. Tornadoes
Warm air is forced upward causing very low pressure on the Earth’s surface
Winds from different directions approach the center, collides and rotates violently
A funnel cloud appears at the base and picks up dirt and debris from the surface

3. Severe Weather
3. Hurricane
Storm w/ wind speed of at least 120 km/hr
Formed by trade wind collisions on surfaces of warm seas
A low pressure area develops
Warm moist air is forced up and cools leading for moisture to condense

4. Pollution
The introduction of substances, biological organisms, or energy into air, water or soil, resulting on a change of its quality, which is likely to affect its normal use or endanger public health and the living environment

5. Pollution
Can be caused by natural processes such as volcanic eruption

6. Effects of Pollution:
Harm organisms thriving in contaminated areas
Reduces the use of contaminated resources
Increase the risk of health hazards to man

7. Sources of Land Pollution
Accidental chemical spills
Improper disposal of chemicals and industrial wastes
Agriculture
Mining and quarrying
Sewage sludge
Household solid wastes
Other physical degradation of land

8. Sources of Water Pollution
Chemicals (acids, heavy metals, pesticides)
Radioactive materials from nuclear plants
Dissolved organic matter
Pathogens (E. coli, coliforms from human excreta)
Nutrients (nitrogen, phosphorus w/c leads to algal blooms)

9. Sources of Air Pollution
Natural phenomena (volcanic eruptions)
Chemicals
CO2 from coal mining, fossil fuel burning
Benzene from gasoline
Asbestos
Sulfates and nitrates from factories and emissions
Smog (Smoke + fog)

10. The Water Cycle

11. The Carbon Cycle

13. It should be noted that air pollutants may also contaminate the soil and water (acid rain)

14. Soil pollutants may also contaminate water (solid waste transported by runoffs).

16. Eutrophication can lead to:
Algal bloom
Increase water turbidity
Depeltion of dissolved oxygen
Heavy detritus deposits at the bottom

17. Toxins can become concentrated in successive trophic levels of food webs
Humans produce many toxic chemicals that are dumped into ecosystems.
These substances are ingested and metabolized by the organisms in the ecosystems and can accumulate in the fatty tissues of animals.
These toxins become more concentrated in successive trophic levels of a food web, a process called biological magnification.

18. The pesticide DDT (dichlorodiphenyltrichloroethane), before it was banned, showed this affect.

20. AGENT
MAN
DISEASE
ENVIRONMENT