Transcript fossilfuels

Fossil Fuels
Fossil Fuels
• Fossil fuel is a general term for buried
combustible geologic deposits of organic
materials, formed from decayed plants and
animals that have been converted to crude oil,
coal, natural gas, or heavy oils by exposure to
heat and pressure in the earth’s crust over
hundreds of millions of years.
Fossil Fuels
• Fossil fuels such as coal, oil and gas come from
materials that absorbed CO2 from the
atmosphere many millions of years ago.
• As fuels they offer high energy density, but
making use of that energy involves burning
the fuel, with the oxidation of the carbon to
carbon dioxide and the hydrogen to water
(vapor).
Fossil Fuels as part of the Carbon Cycle
• Plants use carbon dioxide and sunlight to
make their own food and grow. The carbon
becomes part of the plant. Plants that die and
are buried may turn into fossil fuels made of
carbon like coal and oil over millions of years.
When humans burn fossil fuels, most of the
carbon quickly enters the atmosphere as
carbon dioxide.
Carbon Cycle Diagram
Carbon in Atmosphere
Decomposers
break down dead
things, releasing
carbon to
atmosphere and
soil
Fossil fuels are
burned; carbon
is returned to
atmosphere
Carbon slowly
released from
these substances
returns to
atmosphere
Plants use
carbon to make
food
Plants and
animals die
Bodies not
decomposed —
after many
years, become
part of oil or coal
deposits
Animals eat
plants and
take in carbon
Carbon Footprint
• Everyone has a carbon footprint – the total
amount of greenhouse gases produced to
directly and indirectly support human
activities, usually expressed in equivalent tons
of carbon dioxide (CO2).
• Your carbon footprint is the sum of all
emissions of CO2, which were induced by your
activities in a given time frame.
Carbon Footprint
• The carbon footprint is a very powerful tool to
understand the impact of personal behavior
on global warming. Most people are shocked
when they see the amount of CO2 their
activities create! If you personally want to
contribute to stop global warming, the
calculation and constant monitoring of your
personal carbon footprint is essential.
Reduce Your Carbon Footprint
Typical Household Carbon Footprint