(a) Explain four reasons for which temperature decreases with height within the troposphere. (b) With the aid of a diagram, describe the mode of formation o...
(a) Explain four reasons for which temperature decreases with height within the troposphere. (b) With the aid of a diagram, describe the mode of formation of orographic rainfall.
(a) The four reasons for which temperature decreases with height within the troposphere are:
Decrease in air pressure: As altitude increases, air pressure decreases. When air pressure decreases, air molecules become more spread out, leading to a decrease in temperature. This is known as adiabatic cooling.
Decrease in greenhouse gases: The concentration of greenhouse gases such as carbon dioxide and water vapor decreases with height. These gases trap heat in the lower atmosphere, leading to higher temperatures. When the concentration of these gases decreases, less heat is trapped, leading to a decrease in temperature.
Decrease in solar radiation: The amount of solar radiation that reaches the Earth's surface decreases with altitude. This is because the atmosphere absorbs and scatters some of the solar radiation before it reaches the surface. As a result, the Earth's surface is warmer than the upper atmosphere, leading to a decrease in temperature with height.
Vertical mixing: The troposphere is characterized by vertical mixing, which occurs when warm air rises and cool air sinks. As a result, heat is transported from the surface to higher altitudes, leading to a decrease in temperature with height.
(b) Orographic rainfall is formed when moist air is forced to rise over a mountain range. As the air rises, it cools and condenses, leading to the formation of clouds and ultimately, precipitation.
The process of orographic rainfall can be explained using the following diagram:
Mountain Range
/ \
/ \
Warm, moist air Dry, cool air
Warm, moist air approaches the mountain range.
The air is forced to rise over the mountain range.
As the air rises, it cools adiabatically, leading to the formation of clouds.
The clouds release their moisture as precipitation on the windward side of the mountain range.
The air descends on the leeward side of the mountain range, leading to adiabatic warming and a decrease in relative humidity.
As a result, the leeward side of the mountain range experiences dry conditions, known as a rain shadow.
In summary, orographic rainfall is formed when moist air is forced to rise over a mountain range, leading to adiabatic cooling and the formation of clouds and precipitation.
(a) The four reasons for which temperature decreases with height within the troposphere are:
Decrease in air pressure: As altitude increases, air pressure decreases. When air pressure decreases, air molecules become more spread out, leading to a decrease in temperature. This is known as adiabatic cooling.
Decrease in greenhouse gases: The concentration of greenhouse gases such as carbon dioxide and water vapor decreases with height. These gases trap heat in the lower atmosphere, leading to higher temperatures. When the concentration of these gases decreases, less heat is trapped, leading to a decrease in temperature.
Decrease in solar radiation: The amount of solar radiation that reaches the Earth's surface decreases with altitude. This is because the atmosphere absorbs and scatters some of the solar radiation before it reaches the surface. As a result, the Earth's surface is warmer than the upper atmosphere, leading to a decrease in temperature with height.
Vertical mixing: The troposphere is characterized by vertical mixing, which occurs when warm air rises and cool air sinks. As a result, heat is transported from the surface to higher altitudes, leading to a decrease in temperature with height.
(b) Orographic rainfall is formed when moist air is forced to rise over a mountain range. As the air rises, it cools and condenses, leading to the formation of clouds and ultimately, precipitation.
The process of orographic rainfall can be explained using the following diagram:
Mountain Range
/ \
/ \
Warm, moist air Dry, cool air
Warm, moist air approaches the mountain range.
The air is forced to rise over the mountain range.
As the air rises, it cools adiabatically, leading to the formation of clouds.
The clouds release their moisture as precipitation on the windward side of the mountain range.
The air descends on the leeward side of the mountain range, leading to adiabatic warming and a decrease in relative humidity.
As a result, the leeward side of the mountain range experiences dry conditions, known as a rain shadow.
In summary, orographic rainfall is formed when moist air is forced to rise over a mountain range, leading to adiabatic cooling and the formation of clouds and precipitation.