The greenhouse effect works similarly to an ordinary greenhouse, trapping heat from sunlight within the atmosphere. Greenhouse gases like carbon dioxide trap heat in the atmosphere, causing the Earth's average temperature to rise 0.6°C since the late 1800s. It is widely believed that increasing concentrations of greenhouse gases from human activities are the dominant cause of current global warming. Too much of the greenhouse effect can have severe consequences, as seen on the planet Venus which has a surface temperature of 460°C due to its dense carbon dioxide atmosphere.

1. In
an
ordinary
greenhouse,
sunlight
passes
through
the
glass
walls
and
warms
up
the
inside.
This
heat
then
gets
trapped
within
the
walls.
The
greenhouse
effect
in
the
atmosphere
works
a
little
bit
like
an
ordinary
greenhouse.
Greenhouse
gases
trap
the
heat
brought
by
light
passing
through
the
atmosphere
of
the
Earth.
The Earth has warmed an
average of 0.6 o
C (1.1 o
F)
since the beginning of the
Industrial Revolution in
1880.
-­‐
It
is
widely
thought
that
the
increase
in
temperature
is
largely
caused
by
the
human-­‐
induced
increase
of
greenhouse
gas
concentrations
in
the
atmosphere.
Too
much
greenhouse
effect
also
has
consequences.
Venus
has
an
atmosphere
of
96%
carbon
dioxide
(CO2),
and
a
surface
temperature
of
460
0
C!
Only
0.04%
of
Earth’s
atmosphere
is
CO2.
On
Earth,
most
CO2
is
stored
in
sedimentary
rocks,
but
on
Venus,
most
carbon
is
in
the
atmosphere!
THE GREENHOUSE EFFECT
The data in the graph above show that temperatures
have risen and fallen with CO2 concentrations over the
last 400,000 years. Gas bubbles from ice cores show that
there is now 36% more CO2 in the atmosphere compared
to any time in the last 650,000 years.