DAILY CURRENT AFFAIRS QUIZ – 15 November 2024

Ans. b

Explanation:

Normal Temperature Conditions:

• Under typical circumstances, temperature decreases as altitude increases within the troposphere at a rate of 1 degree for every 165 meters. This pattern is known as the normal lapse rate.

Temperature Inversion:

Statement 1: Incorrect

• In standard conditions, colder air usually resides above warmer air due to the typical temperature decrease with height. However, during a temperature inversion, there’s an atypical reversal where a layer of warm air rests above a layer of cooler air. Contrary to the initial statement, temperature inversions are typically short-lived events.

Statement 2: correct

• Clear, cloudless skies create ideal conditions for temperature inversion as they allow unimpeded radiation release. Additional favorable circumstances for temperature inversions include long winter nights, dry air close to the ground, slow air movement, and a surface covered in snow.

Statement 3: correct

• Temperature inversion significantly influences cloud formation, precipitation, and visibility. Visibility often decreases below the inversion due to the build-up of dust and smoke particles. Additionally, the cooler air near the base of an inversion can lead to the formation of fog in those areas.

Ans. a

Explanation:

Geostrophic Wind:

1. Concept of Geostrophic Wind

• Definition: Geostrophic wind emerges from the precise equilibrium between the Coriolis force and the pressure gradient force within atmospheric science.
• Geostrophic Equilibrium: This state, known as geostrophic equilibrium or balance, signifies the condition where the geostrophic wind develops.

2. Direction and Relation to Isobars

• Geostrophic Wind Direction: It flows parallel to the isobars, representing lines of constant pressure.
• Natural Variances: Geostrophic balance rarely remains exact in nature due to additional forces like ground friction.

3. Differences from True Wind

• True Wind vs. Geostrophic Wind: Actual winds typically deviate from the geostrophic wind due to factors such as ground-based friction.
• Conditions for Equality: The actual wind would mirror the geostrophic wind solely in the absence of friction, for instance, above the atmospheric boundary layer, and in the scenario of perfectly straight isobars.

Ans. d

Explanation:

Tropical Cyclones: Characteristics and Factors

1. Nature and Impact

• Description: Violent storms originating over tropical oceans, causing significant devastation upon reaching coastal areas due to fierce winds, intense rainfall, and storm surges.

2. Wind Movements in Tropical Cyclones

• Statement 1 (Incorrect): Wind patterns within tropical cyclones run counterclockwise in the northern hemisphere and clockwise in the southern hemisphere, attributed to the Coriolis Force.

3. Conditions Favorable for Formation

• Statement 2 (Correct): Favorable conditions for tropical cyclone genesis include expansive warm sea surfaces with temperatures surpassing 27°C, sufficient Coriolis force to generate a cyclonic vortex, minimal fluctuations in vertical wind speed, presence of a pre-existing weak low-pressure zone, and upper-level divergence over the sea.

4. Characteristics of the ‘Eye’

• Statement 3 (Correct): The ‘eye’ represents a circular region within a severe tropical cyclone, characterized by relatively calm winds and fair weather. It typically lacks precipitation and occasionally displays clear skies or star visibility. The eye denotes the area with the lowest surface pressure and highest temperatures at upper levels.

Ans. a

Explanation:

Atmospheric Layers and Characteristics:

1. Troposphere – Dominant Atmospheric Layer

• Description: Closest layer to the planet, comprising approximately 80% of the total atmospheric mass.
• Temperature and Water Vapor: Temperature and water vapor content decrease swiftly with altitude.
• Water Vapor Concentration: Contains 99% of the atmospheric water vapor, varying across latitudes. Concentration peaks in tropical regions (up to 3%) and diminishes towards the poles.

2. Mesosphere – Cooling Layer with Coldest Temperatures

• Location: Extends from around 30 to 50 miles (50 to 85 km) above the Earth’s surface.
• Temperature Variation: Features decreasing temperatures; the mesopause, its upper boundary, hosts the coldest temperatures in Earth’s atmosphere, especially evident in summer near the pole.

3. Exosphere – Outermost Atmospheric Region

• Position: Situated as the furthest atmospheric region from Earth’s surface.
• Escape Probability: Molecules in the exosphere may escape into space if moving fast enough or be drawn back to Earth by gravity if not, with minimal chances of collision.
• Boundary and Transition: Lower boundary, known as the thermopause or exobase, fluctuates from approximately 150 to 300 miles (250-500 km) based on solar activity. Represents a transitional zone between Earth’s atmosphere and interplanetary space.

Ans. d

Explanation:

Air Pressure Dynamics:

• When heated, air expands, and when cooled, it contracts, leading to fluctuations in atmospheric pressure. These pressure variances prompt the movement of air from areas of high pressure to those of low pressure, initiating air circulation. Moreover, atmospheric pressure plays a critical role in determining whether air will ascend or descend.

Statement 1: Incorrect

• Contrary to the statement, within the lower atmosphere, pressure actually decreases rapidly rather than increases with height. However, this decline in pressure isn’t consistent due to the variability of factors influencing air density, such as temperature, moisture content, and gravitational effects. Consequently, establishing a straightforward relationship between altitude and pressure becomes challenging.

Statements 2 and 3: correct

• Atmospheric pressure isn’t consistent across all locations. The Earth’s surface experiences diverse pressure changes due to uneven surface heating. Analyzing the horizontal pressure variations involves plotting lines, known as isobars, connecting areas sharing identical pressure values on maps. Isobars represent the horizontal distribution of pressure at consistent levels. To standardize pressure measurements for comparison, adjustments are made by calculating pressure at different stations and reducing it to sea level to neutralize altitude-based effects.