QuizAtmosphere Quiz – 1EPASeptember 8, 2025September 8, 2025no commentNo tags13views Atmosphere-Quiz-1 1 / 15 Which of the following best explains the reason why the troposphere is the most unstable layer of the atmosphere? Presence of ozone heating the layer Direct heating from the Earth’s surface Absence of water vapour Strong Coriolis effect The troposphere is heated from below as Earth’s surface absorbs solar radiation and re-radiates it as long-wave radiation. This heating causes convection and turbulence, making it unstable. 2 / 15 The presence of which gas absorbs most of the outgoing long-wave terrestrial radiation? Nitrogen Oxygen Carbon dioxide Argon CO₂ strongly absorbs long-wave terrestrial radiation (infrared), making it a major greenhouse gas. Nitrogen and oxygen are mostly transparent to it. 3 / 15 Which of the following is correct about “Thermal Equator”? It coincides with the Equator (0° latitude) It shifts seasonally north and south of Equator It is located permanently at 23.5°N It coincides with ITCZ at all times The thermal equator is the zone of highest mean annual temperature, which shifts with the Sun’s apparent movement (north in June, south in December). It rarely coincides with the actual equator. 4 / 15 Atmospheric temperature inversion is most likely to occur: During clear nights with calm winds During strong convection in the afternoon In upper stratosphere due to ozone Over equator during daytime At night, rapid cooling of the ground causes lower air to cool more than the upper air, leading to temperature inversion. Calm conditions enhance it. 5 / 15 The exosphere is primarily composed of: Oxygen and Nitrogen Ozone and Argon Hydrogen and Helium Carbon dioxide and Methane The exosphere is the outermost layer where light gases like hydrogen and helium dominate and may even escape Earth’s gravity. 6 / 15 Which layer of the atmosphere contains the “homopause,” a boundary where molecular diffusion becomes more important than turbulent mixing? Lower troposphere Near stratopause At ~100 km altitude Above exosphere The homopause (around 100 km) separates the homosphere (well-mixed gases) from the heterosphere (layered gases by molecular weight). 7 / 15 The lapse rate in the troposphere is about: 4.5 °C/km 6.5 °C/km 10 °C/km 12 °C/km The environmental lapse rate in the troposphere averages 6.5 °C/km, though it varies with moisture and location. 8 / 15 Jet streams are found in which atmospheric layer? Troposphere Lower stratosphere Mesosphere Thermosphere Jet streams occur near the tropopause, at the boundary of troposphere and stratosphere (about 9–12 km altitude in mid-latitudes). 9 / 15 Which of the following gases has the highest residence time in the atmosphere? Methane Water vapour Nitrous oxide Carbon dioxide Water vapour has very short residence time (days), methane ~12 years, nitrous oxide ~120 years, but CO₂ has the longest (hundreds of years), making it most persistent 10 / 15 Atmospheric pressure decreases with height, but not at a uniform rate. The main reason is: Density of air decreases with height Ozone concentration increases with height Latent heat release from clouds Gravity varies with altitude Pressure decreases rapidly at lower levels due to high air density, but more gradually at higher altitudes where density is very low. Hence, it’s not uniform. 11 / 15 The ionosphere is significant for: Reflection of short-wave radio signals Absorption of visible light Causing monsoon rainfall Regulating trade winds The ionosphere contains charged particles that reflect radio waves back to Earth, enabling long-distance communication 12 / 15 The tropopause is higher over the equator than over the poles primarily because: Earth’s rotation speed is highest at equator Strong convection due to high solar heating Coriolis force weakens air circulation More ozone at equator Over the equator, intense solar radiation drives strong convection currents, pushing the tropopause higher (~16–18 km) compared to poles (~8–10 km). 13 / 15 The upper limit of the mesosphere is characterized by: Maximum temperature due to UV absorption Lowest temperatures in the atmosphere High concentration of greenhouse gases Neutral equilibrium of air masses The mesopause (upper limit of mesosphere) has the coldest temperatures (about –90°C) because there is no significant ozone or greenhouse gas absorption of radiation. 14 / 15 The “ozone hole” is most prominent over Antarctica due to: High UV radiation from Sun Presence of Polar Stratospheric Clouds Low atmospheric pressure Greater volcanic activity PSCs provide a surface for chemical reactions that release chlorine radicals from CFCs, which destroy ozone. Cold conditions over Antarctica enhance PSC formation, making the ozone hole prominent there. 15 / 15 The stratopause marks the boundary between: Troposphere and Stratosphere Stratosphere and Mesosphere Mesosphere and Thermosphere Exosphere and Ionosphere The stratopause is the boundary between the stratosphere (where temperature increases with height due to ozone absorption) and mesosphere (where temperature again decreases with height). Your score is The average score is 24% 0% Restart quiz share on Facebookshare on Twitteradd a comment Leave a Response Cancel replyCommentName Email Save my name, email, and website in this browser for the next time I comment. The Ultimate Guide to CUET Commerce 2027
