Q.3.Consider the following statements :

1. Water vapour is a variable gas in the atmosphere, which decreases with altitude.

2. In the warm and wet tropics, it may account for four per cent of the air by volume, while in the dry and cold areas of desert and polar regions, it may be less than one per cent of the air.

3. Water vapour increases from the equator towards the poles.

4. Water vapour contributes to the stability and instability in the air.

Q.1. Consider the following statements :

1. Dust particles are generally concentrated in the lower layers of the atmosphere; yet, convectional air currents may transport them to great heights.

2. The higher concentration of dust particles is found in subtropical and polar regions due to dry winds in comparison to equatorial and temperate regions.

3. Dust and salt particles act as hydrophobic nuclei around which water vapour condenses to produce clouds.

Q.2.Which of the following represents the correct descending order of the top four most abundant gases in Earth's atmosphere by percentage composition ?

A. Nitrogen > Oxygen Argon > Carbon Dioxide

B. Oxygen Nitrogen Argon > Carbon Dioxide

C. Nitrogen Carbon Dioxide Oxygen > Argon

D. Oxygen Carbon Dioxide > Nitrogen > Argon

Q.3.With reference to the layers of the atmosphere, consider the following statements :

1. The thickness of the troposphere is greatest at the equator because heat is transported to great heights by strong convectional currents.

2. The air temperature at the tropopause is about -80°C over the poles and about -45°C over the equator.

3. In the mesosphere, temperature starts decreasing with the increase in altitude and reaches up to -100°C at a height of 80 km.

4. Radio waves transmitted from the Earth are reflected back to the Earth by the ionosphere.

🚀 Accelerate your UPSC journey with our Fast Track Course!

📚 Designed for ambitious students, this course lets you learn quickly and efficiently, allowing you to watch lectures at 2x speed ⏩️.

Revise and refresh your knowledge in a fraction of the time, and stay ahead of the curve 🏃‍♀️.

💪 Our Fast Track Course is perfect for those who want to make the most of their study time and crack the UPSC exam with confidence.

🧠 With concise and focused lectures, you'll be able to grasp key concepts and retain information more effectively.

⏰ Don't let time constraints hold you back - join our Fast Track Course today and achieve your UPSC goals! 🎯

Learn smart, not hard, and make every minute count ⏱️.

Stay focused, stay motivated, and get ready to ace the exam! 💥

Link: https://courses.sleepyclasses.com/learn/Fast-Track---GS-Mentorship-Course-for-2026

#upsc #SleepyClasses

Q.1. With reference to the Earth's atmosphere, which one of the following statements is correct ?

A. The total amount of insolation received at the equator is roughly about 10 times of that received at the poles.

B. Infrared rays constitute roughly two-thirds of insolation.

C. Infrared waves are largely absorbed by water vapour that is concentrated in the lower atmosphere.

D. Infrared waves are a part of visible spectrum of electromagnetic waves of solar radiation.

Q.2.With reference to the Spatial distribution of insolation at the Earth's surface, consider the following statements :

1. The insolation received at the surface varies from about 70 Watt/m2 in the tropics to about320 Watt/m2 in the poles.

2. Maximum insolation is received over the subtropical deserts, where the cloudiness is the least.

3. Equator receives comparatively more insolation than the tropics.

4. Generally, at the same latitude the insolation is more over the continent than over the oceans,

Q.3. With reference to the variation in the net heat budget at the Earth's surface, consider the following statements :

1. There is a surplus of net radiation balance between 40 degrees north and south and the regions near the equator have a deficit

2. The surplus heat energy from the tropics is redistributed pole wards and as a result the tropics do not get progressively heated up due to the accumulation of excess heat or the high latitudes get permanently frozen due to excess deficit.

Unlock your potential and achieve your dreams with our exclusive PPSC 2025 strategy session!

Join Dr. Manmeet Kaur on August 29th at 5:00 PM and gain the insights you need to succeed.

Believe in yourself, take the leap, and let your hard work pay off.

Don't miss this opportunity to transform your preparation and crack the PPSC 2025 with confidence.

Mark your calendars and get ready to take the first step towards your success!

Register here 🔗 https://sleepyclasses.com/punjab-pcs-prelims-2025-strategy/?source=Telegram

Q.1.Temperature inversion occurs when the normal lapse rate is reversed and the temperature increases with height rather than decreasing.

Consider the following statements regarding this phenomenon :

1. A long winter night with clear skies and still air is an ideal situation for inversion.

2. Surface inversion promotes instability in the lower layers of the atmosphere.

3. Over polar areas, temperature inversion is normal throughout the year.

4. Air drainage inversion in hilly areas helps protect plants from frost damage.

Q.3.The global distribution of temperature can well be understood by studying the temperature distribution in January and July. The temperature distribution is generally.

Consider the following statements in context with the same :

1. In January the isotherms deviate to the north over North Atlantic Ocean and to the south In Europe.

2. The presence of cold ocean currents, Gulf Stream and North Atlantic drift, make the Northern Atlantic Ocean cold and the isotherms bend towards the north.

3. Over the land the temperature decreases sharply and the isotherms bend towards the south in Europe.