Environmental Issues

1
Environmental Issues

• Human Impact on the Environment

2
Oops

• Humans did not set out to ruin the biosphere
  (area of planet that sustains life)
• Some choices we have made have had negative
  effects on the environment and we need to address
  them

3
Acid Rain

• SULFUR introduced into the atmosphere by
  smokestacks from factories can combine with water
  vapor to produce SULFURIC ACID
• Sulfuric acid is carried to the earths surface
  in acidified precipitation called ACID RAIN
• Acid Rain has a pH that falls below 5.0

4
Ozone Depletion

• The decrease in the earths OZONE LAYER allows
  more UV rays to reach the earths surface.
• This has caused an increase in SKIN CANCER (which
  has nearly doubled since 1980)
• CFCS (CHLOROFLUOROCARBONS) cause ozone depletion

5
Global Temperature

• The global temperature has been increasing
  rapidly for more than a CENTURY
• Global WARMING is followed by centuries of COLD
• Human activity contributes to global warming
• Warmer temperatures raise sea levels (by melting
  more ice) and decrease agriculture output (by
  affecting weather patterns).

6
Greenhouse Effect

• Bonds in CO2 absorb solar energy
• This traps HEAT within the ATMOSPHERE
• The INCREASE in carbon dioxide (CO2) is from the
  burning of fossil fuels

7
Deforestation

• Clear-cutting of forests causes erosion,
  flooding, and changes in weather patterns.
• The slash-and-burn method of clearing forests for
  agriculture increases atmospheric CO2, which
  contributes to the greenhouse effect.

8
Effects of Chemical Pollution

• Pesticides such as DDT have been used to control
  insects
• The chemicals end up in the water supply
• As molecules pass up the TROPHIC levels, they
  become more CONCENTRATED
• This is called BIOLOGICAL MAGNIFICATION, or
  biomagnification

9
Human Introduction of Organisms

• Nonnative plants and animals that are introduced
  into a habitat where they harm or endanger native
  plants and animals are invader, invasive, exotic,
  or alien species

10
Human Population

• The number of humans inhabiting the Earth is
  rising exponentially
• Longer life spans
• Better food/medicine
• Technology
• When will we run out of space?
• When will we run out or resources?