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These words were spoken by Doctor Martin Summerkorn
Senior Climate Change Adviser for the World Wildlife Arctic Program.
in an effort to motivate the world to take action to counter the changes
occurring in the world's climate.
In studying climate change several questions must be addressed.
When and why did the change start?
What is the evidence to suggest the problem is still occurring and will
probably get worse? And finally, what are the results of any of these changes?
Before we can address any of these questions, must first understand the relationship
between the Earth and Sun's radiation.
Scientists have long known that the presence of an atmosphere to keeps the
surface of the planet warmer
then it would without an atmosphere.
In fact without an atmosphere of the surface of the Earth would be about
thirty degrees celsius
than it is now.
In order to understand why, we need to consider the surface of the Earth and
its atmosphere separately.
Because there ia radiative equilibrium,
we know that the planet emits enough for a long wave radiation
to equal the solar radiation absorbed by it.
However most of the long wave radiation that is emitted
by the planet into space
is emitted by the atmosphere rather than the surface of the Earth beneath it.
Although the surface does admit long wave radiation only about ten percent of this
radiation passes through
the atmosphere and escapes into space.
The rest is absorbed by the clouds and greenhouse gases in the atmosphere.
These greenhouse gases include carbon dioxide,
water,
methane, and CFCs.
the higher the concentration of these gases the more heat is retained
Since we know that the gases in the atmosphere especially the greenhouse
gases,
control the temperature of the Earth
is there any evidence to show that the climate declining is indeed changing.
Global changes in temperature would be indication
of any climate change, so let's look at the data.
This graph shows the global temperature change from the period of 1860
2000.
It is fairly easy to see the trend of the temperature change is increasing and in
fact
accelerating in recent years as evidenced by the increase in the slope
of the data trend.
One cause of the temperature change could be an increase in the greenhouse
gases in the atmosphere.
A record of their concentrations over thousands of years have been found in ice
formations at the poles.
This image shows how the concentration of carbon dioxide has been increasing,
especially recently.
This is a photograph of a typical ice core that has been used to collect data
on the concentrations of carbon dioxide.
After viewing the graphs on changing temperature and carbon dioxide
concentrations
it is apparent that there was a drastic modification to the
environment in the late 1800s, and has been accelerating to this day.
If we take a look back at the past 100 years the environment in the late 1800s. The past one hundred years of the planet's
history
possible cause for these changes is evident.
The Industrial Revolution began in the late eighteen hundreds in England.
It soon spread throughout the world.
The revolution brought about changes in our products were made and distribute to
consumers.
Previous to this time nearly everything was hand made.
In an effort to become more efficient and profitable, new factories and
transportation networks were developed.
This meant that fuels will be needed to supply the power to keep the industry going.
The burning of fossil fuels is a fairly cheap source of energy and both industry
and transportation develop products that used it as you fuel.
Coal has been used to generate electricity to provide heat. Crude oil
has been used not only for these things but also the fuel for the internal
combustion engine.
as the world's population increased, the demand and use of these fuels has
increased producing more carbon dioxide, which was released into the atmosphere.
It is this increased rate of emissions that have been linked to the climate
changes.
The consequences of this environmental change have been far reaching in many
areas of our life. Let's take a few minutes to
enumerate several problems that have become apparent.
One of the results of the rising global temperatures increased number and
severity of storms.
this view from space shows a hurricane that is nearly 250 miles
across with
winds of a150 miles per hour.
This is Hurricane Katrina which devastated the gulf coast in 2005
causing millions of dollars in damage.
Individual families throughout the world
have lost homes
and family
members to these huge storms.
The loss of sea ice and the polar regions as well as a reduction in size of many
glaciers is an environmental concern
among scientists.
Habitats of being destroyed and animal populations are ar risk.
These photographs of the Riggs glacier dramatically demonstrates the
changes that have been occurring.
The rise in temperature of the atmosphere could bring a rise in sea level from the
melting of the sea ice
and from thermal expansion of the water in the oceans.
This diagram of the Chesapeake Bay region show how the rise in sea
level could change the topography of the land.
With the changing weather patterns will come extreme droughts in some regions.
as you can see
entire lakes can be lost and the ground become bone dry.
The lack of water will increase the possibilities of wildfires. Recent
wildfires have been so large that they can be seen from space.
This introductory video on climate change has briefly highlighted how the
Earth and atmosphere absorb energy and how that process could become a potential
problem.
Some of the evidence indicating that the problems are occurring and what may be
causing these problems was introduced.
The effects of a change in climate have far reaching consequences forcing the world
to address this issue