Question

An object is located at a height of \(5 \mathrm{~km}\) from the surface of the earth. The object is located in which part of atmosphere? (a) Thermosphere (b) Mesosphere (c) Stratosphere (d) Troposphere

Short answer

The object is in the Troposphere.

Step-by-step solution

Understanding Atmospheric Layers

The Earth's atmosphere is divided into several layers, each with specific characteristics. These layers, starting from the surface of the Earth, are the Troposphere, Stratosphere, Mesosphere, and Thermosphere.

Identifying Troposphere

The Troposphere is the lowest layer of Earth's atmosphere. It extends from the Earth's surface up to about 8 to 15 kilometers (5-9 miles) depending on the location and time of year. Weather phenomena mostly occur in this layer.

Analyzing Stratosphere

The Stratosphere lies above the Troposphere and extends up to about 50 kilometers (31 miles) above the Earth's surface. It houses the ozone layer and has a relatively stable atmosphere.

Evaluating Mesosphere

The Mesosphere is located above the Stratosphere. This layer stretches from approximately 50 kilometers to 85 kilometers (31 to 53 miles) above the Earth, characterized by decreasing temperatures with altitude.

Inspecting Thermosphere

The Thermosphere is much higher up, starting around 85 kilometers (53 miles) and extending out to about 600 kilometers (373 miles). It is a region with very thin air and high temperatures due to solar activity.

Determining the Correct Layer

At a height of 5 kilometers, the object is located well within the Troposphere, which starts at the Earth's surface and extends upward to as high as 15 kilometers. Thus, the object is located in the Troposphere.

Key concepts

Troposphere

The Troposphere is the first and lowest layer of Earth’s atmosphere. It extends from the Earth's surface up to about 8 to 15 kilometers (5 to 9 miles), depending on the geographical location and time of year. For instance, it is thicker at the equator than at the poles. This layer is where all weather phenomena occur, such as rain, snow, and winds.

Several characteristics define this layer:

• It contains roughly 75-80% of the atmosphere's total mass.
• Temperature decreases with altitude. This means it gets colder as you go higher into the Troposphere.
• It is the densest layer. The air here is full of water vapor and gases that we need to breathe.
• Mixing of air occurs due to turbulent air movements.

The Troposphere is crucial for life since it holds the oxygen vital for living organisms. Due to its direct contact with Earth's surface, it also impacts our immediate environment and weather.

Stratosphere

The Stratosphere is the layer that sits just above the Troposphere, stretching from approximately 15 kilometers up to about 50 kilometers (10 to 31 miles) above Earth.

Key characteristics of the Stratosphere include:

• Temperature increases with altitude, a characteristic that is opposite to the Troposphere.
• It contains the ozone layer, which absorbs and scatters ultraviolet solar radiation.
• This layer is more stable than the Troposphere, with less turbulent mixing.
• It is home to many commercial jet flights due to smoother flying conditions and less weather disturbances.

The ozone layer in the Stratosphere plays a critical role in protecting living organisms from harmful UV radiation. The temperature rise in this layer is due to the absorption of the sun's radiation by the ozone, enabling the Stratosphere to hold relatively warm temperatures despite being up high in the atmosphere.

Mesosphere

The Mesosphere is the cold middle layer of Earth's atmosphere, located directly above the Stratosphere. It extends from around 50 kilometers to about 85 kilometers (31 to 53 miles) above the Earth.

Notable features of the Mesosphere include:

• It is the coldest layer in Earth’s atmosphere, with temperatures dropping as low as -90°C (-130°F).
• Meteors burn up in this layer when entering Earth's atmosphere, creating "shooting stars."
• The air is much thinner and less dense than the Troposphere and Stratosphere.
• It lacks a steady heat source and is characterized by decreasing temperatures with altitude.

This layer is less understood compared to other layers because it is difficult to reach with conventional aircraft or satellites, given its position. The Mesosphere plays a vital role in degrading meteors before they can hit Earth's surface, providing a crucial protective shield in Earth's atmospheric structure.