Atmosphere & Climate: 19 MCQs with answers

Nitrogen and Oxygen

Nitrogen (78%) and Oxygen (21%) together make up about 99% of the atmosphere, making them the two primary and most abundant gases.

Troposphere

The troposphere is the lowest layer, containing most of the water vapour and clouds, and it is where nearly all weather phenomena occur.

Stratosphere

The stratosphere contains a layer of ozone gas which shields the Earth by filtering the Sun's harmful ultraviolet radiation.

Insolation

Insolation is defined as the incoming solar energy from the Sun that is intercepted by the Earth.

Mesosphere

The mesosphere is the layer where most meteorites entering from space burn up due to friction with air particles.

Monsoon

Monsoon is defined as the seasonal reversal in the wind direction during a year, derived from the Arabic word 'mausim' meaning season.

12 kilometres

The troposphere has an average height of about 12 kilometres, extending from the Earth's surface to the tropopause.

Carbon dioxide

The burning of fossil fuels releases gases like carbon dioxide into the atmosphere, which is a major greenhouse gas contributing to climate change.

Carbon footprint

Carbon footprint is defined as the total greenhouse gases released into the atmosphere as a result of human activities, such as energy use, transportation, or production of goods.

False

Auroras occur in the thermosphere, not the exosphere. The exosphere is the uppermost layer characterised by very thin air.

The unequal heating of land and sea, creating a low-pressure area over land

During summer, the Indian landmass heats up faster than the oceans, creating a low-pressure area over land, which draws moist winds from the high-pressure ocean towards the land.

Soil type

The major elements of weather and climate are temperature, precipitation, humidity, wind, and atmospheric pressure. Soil type is not one of them.

Land cools faster than the sea

At night, land cools faster than the sea, creating a high-pressure area over the land and a relatively low-pressure area over the sea, causing wind to blow from land to sea.

Weak and old river embankments

The case study identifies weak and old river embankments (dhūsī bāndh) and construction too close to rivers as human-made factors that aggravated the floods.

Thermosphere

The thermosphere, which includes the ionosphere, helps with radio transmission by reflecting radio waves transmitted from the Earth back towards it.

Monsoon

The traditional Indian seasons are Vasanta, Grishma, Varshā, Sharad, Hemanta, and Śhishira. 'Monsoon' is the name for the rainy season in the modern IMD classification, not a traditional Rtu.

Tamil Nadu

The north-east monsoon winds pick up moisture from the Bay of Bengal and cause rainfall on the eastern coast of India, especially in Tamil Nadu, Andhra Pradesh, and parts of Karnataka.

True

The 'Don't Miss Out' note explicitly states that temperature decreases with altitude only in the troposphere and mesosphere.

False

The north-east monsoon winds are cold and dry and generally do not bring rainfall to most parts of India, except the eastern coast.