▶ Your Answer :
The reading passage contends that the causes
of the Little Ice Age can be fully explained by there theories. On the other hand,
the lecturer brings up several points that contradict this argument.
First, the speaker argues that although it
is true that the number of sunspots decreased during the Little Ice Age, it does
not prove anything. This is supported by the fact that according to recent research when sunspots decreased, the total solar radiation is found to be as same as
before. This means that total sun radiation is not related to the observable
sunspot. This casts doubt on the reading passage’s claim that the Little Ice
Age was triggered by diminished solar radiation reaching the planet.
Second, according to the lecturer, cooling
trend was not triggered by the volcano. This is because even if there were
volcanic eruptions, dust that cover the atmosphere will not last centuries. On the
other side, the Little Ice Age last about 500 years. This refutes the reading passage’s
assertion that massive volcanic eruption caused the Little Ice Age.
The final point made by the lecturer is
that snow and ice are not the only cause of the Earth’s reflection. Actually, clouds
are the main cause of the planet’s reflection. However, since less clouds cover
the atmosphere because of the cooling of the water, overall reflection rate of
the Earth does not significantly rouse. This counters the reading passage’s argument
that the increase in the Earth’s reflectivity caused global cooling. |