3. Throughout its long
history, Earth has warmed
and cooled time and
again. Climate has always
changed according to the
sunlight received. But
since the past century,
another force has started
to influence Earth’s
climate: humanity.
4. Global warming is
the unusually rapid
increase in Earth’s
average surface
temperature over
the past century
primarily due to
the greenhouse
gases released by
people burning
fossil fuels.
What is Global Warming?
5. In Earth’s history before the Industrial Revolution, Earth’s climate
changed due to natural causes unrelated to human activity. These
natural causes are still in play today, but their influence is too
small or they occur too slowly to explain the rapid warming seen
in recent decades.
Why Do Scientists Think Current
Warming Isn’t Natural?
6. Models predict that as the world
consumes ever more fossil fuel,
greenhouse gas concentrations will
continue to rise, and Earth’s average
surface temperature will rise with
them. Based on plausible emission
scenarios, average surface
temperatures could rise between
2°C and 6°C by the end of the 21st
century. Some of this warming will
occur even if future greenhouse gas
emissions are reduced, because the
Earth system has not yet fully
adjusted to environmental changes
we have already made.
How Much More
Will Earth Warm?
7. The impact of global warming
of course has consequences.
Warming modifies rainfall
patterns, amplifies coastal
erosion, lengthens the growing
season in some regions, melts
ice caps and glaciers, and alters
the ranges of some infectious
diseases. Some of these changes
are already occurring.
How Will Earth Respond to Warming
Temperatures?
8.
9. Fossil fuels are a non-renewable
source of energy (destined,
therefore, to run out over time)
and with a great impact on the
environment, since they
represent the main source of
greenhouse gases. When burned
to produce energy, they release
high quantities of CO2 and
other pollutants into the air
Traditional Sources of Energy
10. Fossil energy is the set
of energy resources
deriving from the
transformation process
of organic substances
rich in carbon,
especially vegetables,
buried millions of
years ago in an
anaerobic environment
FOSSIL ENERGY
11. Coal is a non-renewable fossil
fuel that can be extracted in
mines. It is a ready-to-use fuel,
created by fossilized dead plants
on the bottom of swamps
millions of years ago being
heated and pressurized. Coal is
used as a means for electrical
power and making materials
such as tar, plastic and steel.
Coal
12. Natural gas is a non-renewable
fossil fuel used for a number of
different things. Natural gas can
be used as a heating source in
homes, fuel for stoves, and to
run hot water heaters and other
appliances. This energy source
is also used to produce
materials such as steel, brick,
antifreeze, and explosives.
Natural gas is also a fuel source
for transportation. This fuel
source produces fewer harmful
emissions than other sources.
Natural Gas
13. Oil, one of the primary energy sources of the modern world, is a liquid
mixture of different hydrocarbons, which can be found in deposits located in
the upper layers of the so-called earth's crust. Refining petroleum and
producing products using petroleum give off several different emissions,
such as carbon dioxide, carbon monoxide and sulphur dioxide, which can
cause acid rain.
Oil
14. Nuclear energy
Uranium is the main source of
nuclear energy, which is non-
renewable. To process uranium into
nuclear energy, the atoms of
uranium must be split to release their
energy. Nuclear power is primarily
used to provide electricity. When
nuclear energy is produced, there is
hardly any carbon dioxide produced.
However, there is radioactive waste
produced, which can be damaging to
the environment and a detriment to
the health of humans.