STS12: The Science Behind Climate Change

Question 1

refers to a change in the state of the climate
that can be identified by changes in the mean
and/or the variability of its properties and that
persists for an extended period, typically
decades or longer.

Answer 1

Climate Change

Question 2

MILANKOVITCH THEORY

Answer 2

States that as the Earth travels through space around the sun,
cyclical variations in three elements of Earth-sun geometry
combine to produce variations in the amount of solar energy that
reaches the Earth.

Question 3

THE THREE VARYING ELEMENTS ARE:

MILANKOVITCH THEORY

Answer 3

1. Earth’s orbital eccentricity
2. Earth’s axial inclination
3. Direction of the Earth’s axis
   of rotation

Question 4

EARTH’S ORBITAL ECCENTRICITY

MILANKOVITCH THEORY

Answer 4

High eccentricity at perihelion = more solar
radiation, increase in temperature
Reached maximum about 11,000 years ago
(last ice age)
At present, Earth eccentricity = 0.017 (max is
@ 0.07), there is a difference of 6% of amount
of solar radiation during aphelion and
perihelion
At max orbital eccentricity, the difference can
reach to about 20% to 30% more solar
radiation
Current low eccentricity = Earth is in
interglacial period (warming)