Climatology: UPSC Previous Year Questions (Geography)

Explanation

Option (c) is correct: The correct sequence of the different layers of the atmosphere from the surface of the Earth upwards is: Troposphere Stratosphere Mesosphere Ionosphere Troposphere: This is the lowest layer of the atmosphere, extending from the Earth’s surface up to about 8-15 km. It contains most of the Earth’s weather systems and clouds. Stratosphere: Above the troposphere, this layer extends from around 15 km to 50 km. It contains the ozone layer, which absorbs and scatters ultraviolet solar radiation. Mesosphere: Above the stratosphere, the mesosphere stretches from 50 km to 85 km. It is the layer where meteors burn up upon entry into the Earth’s atmosphere. Ionosphere: This is not a distinct layer like the others but rather a region of the atmosphere (spanning from about 60 km to 1,000 km) where ionization of gases occurs. The ionosphere overlaps with the thermosphere and exosphere.

Explanation

The climate data provided, with moderate temperatures and distinct seasonal rainfall patterns, is more in line with the China-type climate found in parts of Eastern Asia. The temperature gradually increases from 3.9°C in January to 27.8°C in July and then decreases towards December. This shows warm summers and cool winters, which is characteristic of the China-type climate, where summers are typically hot and humid and winters are cold and dry.

Explanation

Option (d) is correct: The 1997 Indonesian forest fires were primarily caused by human activities like slash-and-burn agriculture to clear land for plantations, particularly for palm oil production. These fires escalated due to a lack of effective forest management practises. Options (a), (b) and (c) are incorrect:

The greenhouse effect refers to the trapping of heat in the Earth’s atmosphere by greenhouse gases, leading to global warming. While global warming can influence climate patterns, there is no direct evidence linking the greenhouse effect as the immediate cause of the 1997 fires. The ozone layer protects the Earth from harmful ultraviolet radiation. Its depletion is primarily associated with increased UV exposure. Ozone layer depletion does not have a direct connection to forest fires, including those in Indonesia in 1997. El Niño is a climatic phenomenon characterized by the warming of sea surface temperatures in the central and eastern Pacific Ocean, leading to significant weather changes globally. But it is not directly associated with Indonesian forest fires.