The reading claims that scientists have long wondered what caused the Little Ice Age and provides three possible causes of support.

The reading claims that scientists have long wondered what caused the Little Ice Age and provides three possible causes of support. In contrast, the professor states that the arguments in the passage are outdated and the scientists have new information about the causes. He refutes each of the author's causes and he says none of the ideas presented in the passage could cause the Little Ice Age. First, the article avers that the cooling may have been caused by disrupting of ocean currents. However, the speaker opposes this point by saying that scientists know that the disrupting of the ocean could cool only Europe and north America, but southern hemisphere is not affected. So, why southern area was affected by the disrupting. So this is not the cause. Second, the passage posits that volcanic eruption could have caused the Little Ice Age because it sends dark clouds of dust and sulfur gas into atmosphere. On the other hand, the lecturer counters this point by stating that it is true that if enough dust send to the atmosphere, it would decrease the temperature but it needs a large amount of dust to produce the effect. In fact, he mentions that people should notice this huge amount of dust such as the snow would be gray, but there is no report like that during the Ice Age. He argus that volcanic eruption seems not strong enough to release a lot of dust. Third, the article asserts that substantial decrease in human population may have contributed indirectly to the cooling of the climate. Conversely, the professor casts doubt on this point by explaining that there was not enough time to cool the climate because of this cause. Actually, he says that forest cut down after growing becuase people needed to plant crops and this will not cause the long term of cooling.