3.
Global Warming
Glaciers are melting, sea levels are rising,
cloud forests are drying, and wildlife is
scrambling to keep pace. It's becoming
clear that humans have caused most of the
past century's warming by releasing heat-
trapping gases as we power our modern
lives. Called greenhouse gases, their levels
are higher now than in the last 650,000
years.
4.
The Intergovernmental Panel on
Climate Change
The Intergovernmental
Panel on Climate Change is
a group of scientists of the
United Nations. This group
meets every few years to
review the latest scientific
findings and write a report
summarizing all that is
known about global
warming.
5.
Causes
Scientists have spent decades
figuring out what is causing
global warming. They've
looked at the natural cycles and
events that are known to
influence climate. But the
amount and pattern of warming
that's been measured can't be
explained by these factors
alone. The only way to explain
the pattern is to include the
effect of greenhouse gases
emitted by humans.
6.
Greenhouse gases
Greenhouse gases are made of water
vapour, carbon dioxide, methane, nitrous
oxide and ozone.
The sunlight enters the atmosphere of the
Earth and it
is reflected back by its surface. Greenhouse
gases prevent the sun radiation from escaping
and trap it in the atmosphere. This is one of
the biggest causes of global warming.
8.
Greenhouse gases
There are several gases responsible for
warming, and humans emit them in a variety of
ways. Most come from the combustion of fossil
fuels in cars, factories and electricity power
plants. The gas responsible for the most
warming is carbon dioxide. Other contributors
include methane released from landfills and
agriculture, nitrous oxide from fertilizers and
gases used for refrigeration and industrial
processes, and the loss of forests.
9.
Effects
• Ice is melting
worldwide, especially at the
Earth’s poles.
• Some species will be lead to
extinction.
• Natural disasters will
become stronger.
• Less fresh water will be
available.
10.
What can we do?
We can increase the amount of gases
we take out of the atmosphere. Plants
and trees absorb carbon dioxide as
they grow, "sequestering" carbon
naturally.
We should avoid to use cars and try to
change to electrical cars.
Clean power plants are also the way to
go.
11.
Conclusion
In the end, whether you believe
climate change is naturally
occurring or hastened by man's
footprints, the truth remains
that there are many ways to
combat climate change, and
they all begin with you. We all
must take responsibility for our
actions and learn to live
sustainably, for us, our future
and our world.
12.
Global Warming – “Images”;
Global Warming – “Wikipedia”;
Global Warming – “Natural Resources Defense
Council”
News about Global Warming – “ The Telegraph”
http://topics.nytimes.com/top/news/science/topic
s/globalwarming/index.html - “The New York
Times – Science (Global Warming)”
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